Exhibit 99.1 Global Eco-friendly Future Materials Provider Earnings Release Q2 2023 July 24, 2023

2 / 19 Disclaimer This presentation was prepared and circulated to release the informations regarding the company’s business performance to shareholders and investors prior to the completion of auditing for the period of the second quarter 2023. As figures in this presentation are based on unaudited financial statements, certain contents may be subject to modification in the course of auditing process. This presentation contains certain forward-looking statements relating to the business, financial performance and results of the company and/or the industry in which it operates. The forward-looking statements set forth herein concern future circumstances and results and other statements that not historical facts, and are solely opinions and forecasts which are uncertain and subject to risks. Therefore, the recipients of this presentation shall be aware of that the forward-looking statements set forth herein may not correspond to the actual business performance of the company due to changes and risks in business environments and conditions. The sole purpose of this presentation is to assist persons in deciding whether they wish to proceed with certain investments to the company. The company does not make any representation or warranty, expressly or impliedly, as to the accuracy and completeness of this presentation or of the information contained herein and shall not have any liability for the informations contained in this presentation.

3 / 19 Contents Consolidated Business Performance Major Business Activities Business Performance by Major Areas Appendix

4 / 19 Consolidated Business Performance 1) Recovery of KRW 1 trillion OP and profit normalization , following full operation of Pohang Steel Works QoQ Income Financial Structure QoQ 13.3% +0.3%p 13.0% (KRW Billion) (KRW Trillion) 23,010 12.8% 20,121 +740 19,381 Revenue Net Debt Ratio 9.1% +0.3 8.0 OP Margin 6.7% 7.7 +3.0%p 2,098 Operating Profit 7.5 Net Debt 3.6% 9,238 +621 1,326 EBITDA 3.1 +0.6 705 2.3 1.7 ’22.2Q '23.1Q ’23.2Q ’22.2Q '23.1Q ’23.2Q ＊ Cumulative CAPEX for 2023 (until June): KRW 3.7 tril.(consolidated), 0.5 tril.(separated) 【Before Inter-company Transaction Adjustment】 Revenue Operating Profit (KRW Billion) ‘22.2Q '23.1Q '23.2Q '22.2Q '23.1Q '23.2Q QoQ QoQ 19,331 15,770 16,547 1,762 338 1,021 Steel +777 +683 2) 11,871 9,622 10,298 +676 1,322 251 841 POSCO +590 6,463 5,268 5,210 △58 315 19 93 Overseas Steel +74 18,641 13,870 15,195 +1,325 484 382 445 Green Infrastructure +63 3) POSCO International 10,747 8,306 8,865 +559 346 280 357 +77 3) POSCO E&C 2,490 2,364 2,591 +227 126 55 56 +1 Green Materials 810 1,162 1,194 +32 48 10 4 △6 3) POSCO Future M 803 1,135 1,193 +58 55 20 52 +32 1) average consolidated OP of the steel sector for 14 quarters from ’20 to ’23.1H amounted KRW 1,019 billion 2) POSCO, separated 3) POSCO Energy result included in POSCO International, consolidated

5 / 19 Major Business Activities Release of Low-Carbon Steel Products Released of Renewable energy steel ('23.1Q) and Greenate certified steel ('23.2Q) 【 Carbon Reduced Steel Product Lines】 Product Lines Description ‘23 Procure renewable energy such as solar, wind, Renewable energy steel Provide certificate of renewable energy use Reduce carbon emissions through low-carbon processes/technologies, TM certified steel Allocate the carbon savings to certain products Reduce carbon by using the latest and large EAF and Hybrid low-carbon production 1) ‘26 EAF Type method with blast furnaces carbon TM Reduce carbon by applying technologies of increasing scrap rates from current blast reduced steel Type undecided furnaces (the technology is under review) TM carbon reduced steel Reduce carbon by applying Hydrogen Reduction Ironmaking technology, ‘30 2) HyREX (HyREX Type) 1) Electric Arc Furnace (EAF): An electric arc furnace that uses electrical energy to melt metals or alloys 2) HyREX (Hydrogen Reduction): Hydrogen reduction ironmaking technology

6 / 19 Major Business Activities Expanding Production for Eco-friendly Industries High-grade NO capacity expansion of 300k tons in Gwnagyang for motor cores in eco- friendly cars, targeting to start operation in 4Q (Started construction in April, ’22; existing production capacity: 100k tons at Pohang Steel Works) (‘30) 4 mil. (‘30) 90 mil. (‘20) 75 mil. Internal Combustion Engine Vehicle Production (‘30) 60% (‘20) 0.4 mil. Eco-friendly Vehicle Production (‘20) 9% (POSCO forecast) * High-grade NO(Non-Oriented Electrical Steel) : specification for silicon(≥3.3%) and thickness(≤0.3mm)

7 / 19 Major Business Activities Hydrogen Projects for HyREX POSCO Holdings-led global consortium acquired exclusive rights for development and operation of Green hydrogen business in Duqm, Oman for 47 years § Targeting 500k tons of hydrogen production by 2030, progressing diverse projects aligned with anticipated hydrogen demand - Domestic hydrogen production utilizing CCUS, Green hydrogen project development (Oman, Austrailia, Malaysia, etc.), and participation in Blue hydrogen projects(Saudi Arabia, United States, etc.) § Plan to utilize overseas-produced hydrogen for production of eco-friendly ironmaking raw materials, or domestically adopt it for steelmaking/power generation Oman Project 2 Site • 340km (Equivalent to ½ the area of Seoul, excellent site scalability) Consortium• POSCO Holdings, ENGIE (France), Samsugn Engineering, KOSPO(Korea), EWP(Korea), PTTEP(Thailand) • Renewable energy (Capacity : Solar/Wind approx. 5GW) Equipment • Hydrogen production (Green hydrogen 220k tons) • Ammonia production (Green ammonia 1.2 mil. tons) Plan • Feasibility study(~’24) → Construction(’27~) → Production(’30) [ Location ] [ Site View ] Ammonia Designated Production Site (Duqm) Saudi Arabia Om Oma an n

8 / 19 Major Business Activities Nickel JV for Battery Business Entered joint ventures with leading nickel smelting companies such as CNGR for collaborative businesses in Pyro/Hydrometallurgy of nickel in Indonesia and domestic refining/precursors § Target to complete construction in 2025 for Pyro/Hydrometallurgical refining plants in Indonesia § Aim to establish a stable supply chain by completing the nickel-precursor-cathode value chain in Pohang in collaboration with CNGR, a global precursor leader 3) Pyrometallugy JV in Indonesia Hydrometallurgy JV in Indonesia Domestic refining/precursor JV Location• Halmahera, Indonesia• Sulawesi, Indonesia• Pohang, Korea (Yeongil Bay Industrial Complex) Structure • POSCO Holdings 49%, Partner 51%• POSCO Holdings 20%, Partner 80%• POSCO Holdings 60%, CNGR 40% (refining) 1) 2) Capacity• 52k tons of nickel matte• 62k tons of Nickel MHP• 50k tons of high purity nickel Proress • Joint venture contract signed (in May)• Approved by the Board (in June)• Joint venture contract signed (in June) 1) Matte : Nickel intermediate with 65-75% nickel purity 2) MHP : Nickel intermediate with 40% nickel purity 3) Precursor business is a joint venture between P-Future M / CNGR POSCO Group Nickel Business Strategy Nickel Global Supply Chain Status Pyrometallurgical Base Posco Refining “A leading eco-friendly high purity nickel provider” Hydrometallugical Base (collaborating with SNNC) 4) Refining JV with CNGR 240 (k tons) Preemptive Expedite procurement of nickel intermediate materials (Matte, MHP) Acquirement Pyrometallurgical JV 143 Hydrometallugical JV Additional procurement of low- ESG friendly carbon hydrometallurgical smelting 140 Refining 41 60 Economic [Indonesian) Cost-advantage 20 [Non-Indonesian) IRA compliant Value Hydrometallugical JV (RNO) 2024 2026 2030 4) Quantity, excluding refining, is secured through joint ventures in precursor and recycling production

9 / 19 Business Performance by Major Areas Steel - POSCO · Production/Sales · Income/Financial Structure - Overseas Steel · PT-KP · PZSS · P-Maharashtra · PY-VINA Green Infrastructure - POSCO International - POSCO E&C Green Materials - POSCO Future M

10 / 19 POSCO Production/Sales Production Sales QoQ QoQ 87.3% Utilization Rate* 84.2% 84.7% +2.6%p (k tons, %) 8,352 +190 8,238 8,851 Sales Volume (k tons) +352 Crude Steel 8,545 8,162 60.1 8,499 Domestic Sales 55.4 +0.7%p Product 54.7 Ratio +178 8,482 8,340 8,304 +0.2%p WTP 28.5 Sales Ratio* 28.3 28.2 '22.2Q '23.1Q '23.2Q '22.2Q '23.1Q '23.2Q * Utilization rate : Crude Steel Production / Crude Steel Capacity * Non-prime and semi-product figures excluded in total sales volume ○ With full recovery of Pohang Steel Works from the flood, ○ Amidst shipment delays caused by rain at the end of June, production volume increased HR·Plate sales increased, WTP sales increased • ‘23. 1.20. Final restoration of all facilities completed (k tons) 【Sales volume by quarter】 • Decrease in CR production due to regular maintenance((P) #1, (K) #2) '22.2Q '23.1Q '23.2Q QoQ 【Production Volume by quarter】 (k tons) CR/Coated 3,516 3,596 3,398 △198 Plate 1,392 1,220 1,393 +173 '22.2Q '23.1Q '23.2Q QoQ HR 2,260 2,244 2,331 +87 Carbon Steel 7,885 7,912 8,011 +99 STS 453 360 435 +75 HR 2,146 2,209 2,373 +164 Slab 112 125 188 +63 CR 3,312 3,535 3,299 △236 Products Sales Volume 8,238 8,162 8,352 +190 WTP 2,230 2,226 2,267 +41 STS 455 391 470 +79 ※ CR/Coated : BP, CG, CR, EG, FH, GO, GO, NO, PO, POSMAC, HGA, HGI

11 / 19 POSCO Income/Financial Structure Income QoQ (KRW Billion) 【Operating Profit QoQ】 (KRW Billion) Revenue 11,871 '23.2Q 10,298 +676 +110 9,622 OP Margin +63 Raw material Decrease in cost decrease, +376 1,322 841 flood losses etc. '23.1Q +41 11.1% ASP +5.6%p Operating Profit 8.2% 841 Production/Sales increased 251 251 +590 volume increase 2.6% • Increase in sales price(carbon steel, KRW Thousand/ton) : 1Q) 1,019 → 2Q) 1,066 (+47) '22.2Q '23.1Q '23.2Q - Sales price increase and exchange rate impact : +52 (KRW Billion) - Sales mix impact with increased HR/Plate sales : △5 '22.2Q '23.1Q '23.2Q QoQ EBITDA 1,915 832 1,419 +587 • Decrease in raw material input cost(carbon steel) : 1Q) average price = 100 → 2Q) 98 ○ With full operational normalization, recovered Gross Profit Margin - Iron ore : 1Q) 100 → 2Q) 95.8 / Coking Coal : 1Q) 100 → 2Q) 100 (Crude Steel Production : QoQ +4.1%) • Business losees by the flood ○ OP increased due to market recovery (KRW Billion) ‘22.4Q '23.1Q '23.2Q QoQ (KRW Trillion) ’22.12/E ’23.3/E ’23.6/E 288 Recovery Cost 69 - △69 Cash Balance 7.6 9.5 9.3 ＊ Inventory Loss 0.5 △6 - +6 Debt 7.8 10.3 10.1 * Reversal of inventory loss amount included

12 / 19 Overseas Steel Subsidiaries Performance PT. Krakatau POSCO Zhangjiagang STS (PZSS) Ÿ Increased profit through expanded HR domestic sales after the start of • Reduced operating loses through specialized product-focused sales the new HR line(‘22.11) amidst low-cost competition - Sales Volume(k tons) : 1Q) 879 → 2Q) 727 *HR Domestic Share(%): 2Q) 77%, +12%p - Sales Volume(k tons) : 1Q) 250 → 2Q) 248 - Sales Price(QoQ) : +14% * [HR] +18% [Plate] +10% - Sales Price(QoQ) : △10.1% 883 773 △73 Revenue 719 646 Revenue 651 616 △35 125 Operating Profit Operating Profit +26 58 53 +6 △29 △53 △27 (USD million) QoQ (USD million) QoQ '22.2Q '23.1Q '23.2Q '22.2Q '23.1Q '23.2Q POSCO Maharashtra PY VINA • Improved OP through expanded sales of high-end automotive and home • Increased export share through diversification of export destinations to appliances products and increased prices mitigate the impact of Vietnam’s economic downturn - Sales Volume(k tons) : 1Q) 363 [Automobile] 176, [Home Appliance]40 - Sales Volume(k tons) : 1Q) Domestic 54, Overseas 32 → 2Q) 352 [Automobile] 187 [Home Appliance] 42 → 2Q) Domestic 47, Overseas 54 - Sales Price(QoQ) : +5.5% - Sales Price(QoQ) : △3.5% 104 388 Revenue Revenue +6 +6 82 76 341 335 Operating Profit Operating Profit 7 △1 20 27 +15 5 4 12 (USD million) (USD million) QoQ QoQ '22.2Q '23.1Q '23.2Q '22.2Q '23.1Q '23.2Q

13 / 19 POSCO International Performance Income Major Activities ○ Global Business(OP 150 (KRW Billion)) QoQ (KRW Billion) 11,747 - Steel : Increased sales of high-profit steel products for wind Revenue and solar power 8,865 +559 • Sales volume to eco-friendly market(k tons) : 1Q) 420 → 2Q) 454 8,306 • OP(KRW Billion) : 1Q) 76.8 → 2Q) 118.8 - Agriculture : Steady production in off-season palm • OP of palm business(KRW Billion) : 1Q) 24.3 → 2Q) 18.4 357 +77 346 Operating Profit 280 - Mobility : Increased orders of Emfree* for motor core based 4.0% +0.6%p on patented technology 3.4% OP Margin 2.9% * Laminate in press by applying adhesive between core layers with automatic equipment in the mold • OP(KRW Billion) : 1Q) 1.0 → 2Q) 6.1 ’22.2Q ‘23.1Q ‘23.2Q ○ Energy(OP 210 (KRW Billion)) - E&P : OP increased due to a high development cost recovery 【Revenue by Business】 ratio, despite sales decrease caused by cyclone in Myanmar ’23.1Q ’23.2Q QoQ (KRW Billion) ’22.2Q ’23.1Q ’23.2Q QoQ Myanmar gas sales(Bcf) 47.6 39.3 △8.3 Myanmar OP(KRW Billion) 67.2 110.0 +42.8 Global Business 10,675 7,020 7,884 +864 Senex Energy sales(Bcf) 6.4 6.5 +0.1 (former Trading) Senex OP(KRW Billion) 12.7 11.7 △1 Energy 1,072 1,286 981 △305 - Power Generation : Despite low demand and a decline in SMP, profit protection through low-cost LNG direct importation • OP(KRW Billion) : 1Q) 53.9 → 2Q) 45.5

14 / 19 POSCO E&C Performance Income Major Activities (KRW Billion) ○ Revenue increased due to speeding up the QoQ construction process, etc. 2,591 • Plant : Slightly decreased due to speeding up the construction +227 Revenue process in 1Q 2,490 2,364 • Infrastructure : Revenue and OP increased by speeding up the construction process, etc. • Construction : Revenue increased by speeding up the Operating Profit 126 +1 construction process, etc. while OP decreased due to 55 56 5.1% additional costs such as development levy 2.3% 2.2% △0.1%p OP Margin ○ Order increase in plants of the group’s LiB business - New order amounts : 1Q) KRW 2.7 tril. → 2Q) KRW 3.1 tril. ’22.2Q ‘23.1Q ‘23.2Q • Plant (KRW 0.6 tril., +0.1 QoQ) : Increased orders for LiB sector nd * Argentina) 2 phase of brine-based lithium(0.3), 【Revenue by Business】 Pohang) Cathode 2-1 phase(0.1), etc. (KRW Billion) ’22.2Q ’23.1Q ’23.2Q QoQ • Infrastructure(KRW 0.1 tril., △0.3 QoQ): Asan Tangjeong Site Prepration(0.1), etc. Plant 592 851 843 △8 • Construction(KRW 2.4tril., +0.6 QoQ) : Success in mega PJTs Infrastructure 397 321 401 +80 and expansion of remodellings Construction 1,170 1,042 1,197 +155 * Asan Tangjeong Apartment Construction (0.6), Uijeongbu Consolidated LaGuardia Apartment Construction (0.5) Seosomun Office 331 150 150 - subsidiaries Construction(0.3), Pyeongchon Hyangchon (Lotte A/Hyundai 4th A) Remodeling (0.3), etc.

15 / 19 POSCO Future M Performance Income Major Activities 1,193 1,135 (KRW Billion) QoQ ○ Cathode : Revenue and OP increased through share expansion of N86 +58 *Exchange rate : KRW/U$ 1,275à1,315 Revenue 803 • Improvement in average price through increased sales proportion of high-priced N86 compared to N65 increased revenue and OP – N86 sales proportion : 1Q) 12% → 2Q) 31% 55 52 +32 – Average price (1Q=100) : 1Q) 100 → 2Q) 122 Operating Profit • Anticipated increase in 3Q sales with N86 single crystal production 6.8% 20 +2.7%p 4.4% OP Margin ○ Anode : Improved profitability due to decrease in raw 1.7% material costs ’22.2Q ‘23.1Q ‘23.2Q • Revenue decreased due to sales decrease for EV (QoQ △15%) • Maintained sales price depite a decline in graphite prices, improved 【Revenue by Business】 profitability due to an increase in operating ratio (KRW Billion) ’22.2Q ’23.1Q ’23.2Q QoQ ○ Profitability recovered through high-profit construction in refractories and negotiation reflecting raw material cycles Cathode materials 417 713 786 +73 • Refractories : Improving sales and profitability through increased Anode materials 47 68 56 △12 maintenance facilities and high-profit construction projects Refractories 139 144 146 +2 • Quicklime/Chemical : Despite limestone price decline, profitability Quicklime/Chemical 200 210 205 △5 increased due to increase in sales price

16 / 19 Appendix Progress in Battery Materials Business Summarized Income Statement Summarized Balance Sheet

17 / 19 Progress in Battery Materials Business Material Company PJT ~ ‘22.E ‘23.1Q ‘23.2Q ‘23.2H ‘24 ‘25 Construction Construction Construction Construction Completion Phase I of Electricity of Electricity (Plant 1. ’22.10, of factory/pond (‘24.2Q.) of Brine (Plant 1. ’23.4) (Plant 2. ’23.5) Plant 2. ’22.12) (1Q) P- Argentina Phase II Construction Completion Approval - Detailed designing of of Brine (’23.6) (‘25.2Q.) (’22.10) Pond/Plant - (UP) Lithium Approval Incorporation Construction Completion Phase II P-Lithium (’22.10) (’22.12) (’23.6) (‘25.2Q.) Brine Solution (DOWN) Plant 2 Plant 1 Construction HQ/Sub Center Completion Completion P- (Plant 2. ’22.8, Plant 1 ’22.11)Completion (‘23.3) (’23.10) (’24.2.) Pilbara Lithum Plant 2 Plant 1 Lithium Ore Test run Test run Construction Construction Solution (‘23.10~) (’24.1~) (’23.1) (’23.4) Construction Completion Iron SNNC (’22.6) (4Q) removal Nickel Construction Construction Construction (Leaching Facility) (Extraction Facility) Completion POSCO Refining (’22.10) (‘23.6) (‘23.3) (4Q) Completion EPA(‘22.12) Normal operation(‘23.5) RAMP UP PLSC UP (’22.8) Recyclin Operation start Initial Products out g Completion(’22.12) Normal operation(‘23.11) - Product Certification - P-HYCM RAMP UP DOWN (‘23.2) (‘23.5) Construction P- Constuction Completion Approval of Electricity Next Silicon SiOx (‘23.6) (‘24.2Q) (‘23.1) Generation (‘23.4Q) Solution

18 / 19 Summarized F/S Consolidated Income Statement (KRW Billion) '22.2Q '23.1Q '23.2Q QoQ Revenue 23,010 19,381 20,121 740 Gross Profit 2,733 1,373 2,034 661 (Gross Margin) (11.9%) (7.1%) (10.1%) (3.0%p) SG&A 635 669 708 39 Operating Profit 2,098 705 1,326 621 (Operating Margin) (9.1%) (3.6%) (6.6%) (3.0%p) Net Profit 1,799 840 776 △64 EBITDA 3,075 1,659 2,275 616 (EBITDA Margin) (13.4%) (8.6%) (11.3%) (2.7%p) EPS (KRW) 20,942 9,575 9,090 △485 No. of outstanding shares [Thousands) 75,849 75,863 75,876 13

19 / 19 Summarized F/S Consolidated Balance Sheet (KRW Billion) '22.2Q '23.1Q '23.2Q QoQ Current Assets 52,147 50,315 50,023 △292 Cash and Cash Equivalents 17,939 19,878 19,704 △174 Accounts Receivable 12,394 11,279 11,498 219 Inventories 17,962 15,028 15,042 14 Non-Current Assets 49,723 52,589 53,070 481 Tangible Assets 30,407 32,641 33,385 744 Intangible Assets 5,222 4,907 4,927 20 Other LT Financial Assets 2,300 2,661 2,693 32 Total Assets 101,870 102,904 103,093 189 Liabilities 43,121 43,400 43,213 △187 Current Liabilities 25,757 22,890 21,750 △1,140 Non-Current Liabilities 17,364 20,510 21,463 953 ※ Total Interest Bearing Debt 25,486 27,620 27,691 71 Shareholders’ Equity 58,749 59,504 59,880 376 Owners of the Controlling Stake 53,256 53,802 54,307 505 Net Debt 7,547 7,742 7,987 245 Net Debt to Equity (%) 0.3%p 12.8% 13.0% 13.3% v4