| Hashed, Inc. | Seoul |
| Hauri, Inc. | Seoul |
| HB Investment Co., Ltd | Seoul |
| Helixmith Co., Ltd | Seoul |
| HelloDigital Co., Ltd | Seoul |
| Hexagon Ventures Co., Ltd | |
| Heybit | Seoul |
| HFR, Inc. | Gyeonggi |
| HHosting | Seoul |
| HIMS Co., Ltd | |
| Hits | Seoul |
| Hivelab | |
| HJS ENG | Gyeonggi |
| HK inno.N Corporation | North Chungcheong |
| HLB Panagene | |
| Honam University | |
| Hongik University | |
| Hosting.kr | Seoul |
| Hostway IDC Co., Ltd | Gyeonggi |
| HOWAT Co., Ltd | North Chungcheong |
| Howon University | |
| HPSP Co., Ltd | Gyeonggi |
| HUBDT Co., Ltd | North Chungcheong |
| HubTech Co., Ltd | Gyeonggi |
| Hunet | Seoul |
| Huons | Gyeonggi |
| Huonslab | |
| HWLAB | Seoul |
| Hyperconnect, LLC | |
| HYU Holdings Co., Ltd | |
| Hyundai IT&E Co., Ltd | Seoul |
| Hyundai Motor Company | |
| Hyupsung University | |
| i-SENS, Inc. | |
| IB96 | Seoul |
| IBI.net | Seoul |
| ICB Co., Ltd | Seoul |
| IDEATEC | Seoul |
| Idience | |
| IDTECK | Seoul |
| Igloo Corporation | Seoul |
| Ikina Games | Seoul |
| iLeadBMS | |
| ILIAS Biologics, Inc. | Daejeon |
| Illimis Therapeutics | |
| Imation | Seoul |
| IMBdx, Inc. | Seoul |
| IMBiologics | |
| IMM Investment | Seoul |
| ImmunAbs, Inc. | |