| Keisen University | |
| Keiwa College | |
| KEN Consulting Co., Ltd | Tokyo |
| Kenichi Ohmae Graduate School of Business | |
| Kenja K.K. | |
| Kenrobotech Corporation | Kagawa |
| Kernel Computer System Co., Ltd | Kanagawa |
| Keyence Corporation | |
| Keyence Corporation | Osaka |
| KEYes Co., Ltd | Fukuoka |
| KG Motors, Inc. | |
| KHD Electronics Co., Ltd | Tokyo |
| KHK Kohara Gear Industry Co., Ltd | Saitama |
| Kiara Co., Ltd | Tokyo |
| Kibi International University | |
| Kids-Way Corporation | Tokyo |
| Kidswell Bio Co., Ltd | Tokyo |
| KiHeiTai Co., Ltd | Tokyo |
| Kindai University | |
| Kindai University Technical College | |
| Kingsoft Japan Co., Ltd | Tokyo |
| Kinjiro Co., Ltd | Tokyo |
| Kinjo Gakuin University | |
| Kinki Macintosh Users Group | Osaka |
| Kinki University - Department of Mathematics | Osaka |
| KinoPharma | |
| Kio University | |
| KIOXIA Corporation | Tokyo |
| Kioxia Holdings Corporation | Tokyo |
| Kipp Financial Technologies Co., Ltd | Tokyo |
| KiQ Robotics Co., Ltd | Fukuoka |
| Kiraboshi Capital Co., Ltd | |
| Kiryu University | |
| KIS Co., Ltd | Tokyo |
| Kisco Co., Ltd | Osaka |
| Kisetsu System Co., Ltd | Hyogo |
| Kissei Pharmaceutical Co., Ltd | |
| Kitakyushu Science and Technology Park | Fukuoka |
| Kitami Institute of Technology | |
| Kitasato University | |
| Kitcut Co., Ltd | Tokyo |
| KiteRa Co., Ltd | Tokyo |
| KIWIinternet | Tokyo |
| KK-NET | Tokyo |
| KM Biologics Co., Ltd | Kumamoto |
| KNC Laboratories Co., Ltd | |
| Knowledge Design Co., Ltd | Tokyo |
| KOA Corporation | Nagano |
| Koala Tech Co., Ltd | Fukuoka |
| Kobayasi Institute of Physical Research | |