| ISOTEC Corporation | Seoul |
| ISTE Co., Ltd | Gyeonggi |
| ISU Abxis Co., Ltd | Gyeonggi |
| IT-Concept | |
| ITDA Platform Co., Ltd | |
| iTEC Technologies Ltd | Seoul |
| ITF Co., Ltd | Gyeonggi |
| ITKEY | Seoul |
| Jaesung Faxctory Automation | |
| Jampick Co., Ltd | Seoul |
| Jawha Electronics Co., Ltd | Seoul |
| JE-AN Electronic Co., Ltd | Seoul |
| Jedex, Inc. | Gyeonggi |
| JEI University | |
| Jeil Pharmaceutical Co., Ltd | |
| Jeju International University | |
| Jeju National University | |
| Jeju National University - Department of Electronic Engineering | Jeju |
| Jeju Technopark | Jeju |
| Jeonbuk National University | |
| Jeonbuk Science College | |
| Jeonju University | |
| Jeonnam State University | |
| Jeonu National University of Education | |
| JESCO Co., Ltd | Gyeonggi |
| JETEMA Co., Ltd | Gangwon |
| Jihoosoft | Seoul |
| Jinju Health College | |
| Jinyoung Contech | Seoul |
| JL Partners | |
| JMI Co., Ltd | Seoul |
| JNPMEDI, Inc. | Incheon |
| Joe Black Security | South Chungcheong |
| Joong-ang Sangha University | |
| Joongbu University | |
| JOYCITY Corporation | Gyeonggi |
| JR Creative Co., Ltd | Seoul |
| JT Corporation | South Chungcheong |
| Jungbonet | Seoul |
| Jungwon University | |
| JUSTEK | |
| Jusung Engineering Co., Ltd | Gyeonggi |
| JUVIC | Seoul |
| JW Pharmaceutical Co., Ltd | |
| K-Startup Grand Challenge | Seoul |
| K.C. Tech Co., Ltd | Seoul |
| K2Webtech Co., Ltd | Seoul |
| Kainos Medicine, Inc. | |
| KAIST Electrical Engineering | Daejeon |
| KAIST Youth Entrepreneurship Investment Holdings | Seoul |