| WealthPark Co., Ltd | Tokyo |
| WeatlhNavi Co., Ltd | Tokyo |
| Web Base Co. | Tokyo |
| Web Factory Corporation | Tokyo |
| Web Frontier | Osaka |
| Web Jingle | Yamagata |
| Web Shizuoka | Shizuoka |
| Web Technology Corporation | Tokyo |
| Web Tokai Co., Ltd | Aichi |
| Web-Habu | Nagasaki |
| WEB-SHARK, Inc. | Osaka |
| Web-Star Japan Co., Ltd | Tokyo |
| WebARENA | Tokyo |
| Webedge Co., Ltd | Tokyo |
| Webeyes | Tokyo |
| Weblife Co., Ltd | Tokyo |
| Webmate | Tokyo |
| WebMonkey Corporation | Tokyo |
| Weboss Co., Ltd | Hokkaido |
| WebSmart Co., Ltd | Tokyo |
| Webthor Co., Ltd | Tokyo |
| Webzen Japan Co., Ltd | Tokyo |
| WeCode-inc | |
| Weekday Co., Ltd | Tokyo |
| Weid Co., Ltd | Tokyo |
| Wellnet Corporation | Hokkaido |
| WellThera Co., Ltd | Tokyo |
| Weru Investment Co., Ltd | Tokyo |
| wesionaryTEAM Co., Ltd | |
| WHOIS Corporation | Tokyo |
| Wicresoft Co., Ltd | Tokyo |
| WIDE Project | |
| Will Media Co., Ltd | Tokyo |
| Windabaft Co., Ltd | Tokyo |
| Wing Co., Ltd | Tokyo |
| Wire and Wireless Co., Ltd | Tokyo |
| Wireless Tsukamoto Co., Ltd | Tokyo |
| Wisbrain | Tokyo |
| Wise Impact Co., Ltd | Hyogo |
| WISNET | Tokyo |
| WIT Lab | Tokyo |
| WIXI, Inc. | Tokyo |
| Wiz Corporation | Osaka |
| Wiz Software Corporation | Osaka |
| Wiz Tech Co., Ltd | Tokyo |
| WiZaaS Co., Ltd | Tokyo |
| Wizard | Tokyo |
| Wizard System Laboratory Co,. Ltd | Tokyo |
| Work Style Tech Co., Ltd | Tokyo |
| Worker Bee Co., Ltd | Tokyo |