Mitsui Knowledge Industry Co., Ltd. (三井情報株式会社, Mitsui Jōhō Kabushiki-gaisha) is a Japanese company headquartered in Tokyo, Japan, that offers IT services.

Originally, in 1991, 3Com Japan Corp. was established by Mitsui & Co. and 3Com Corp.

[3] The company offers the services of system integration, cloud computing, information security, and IT lifecycle support in Japan and mostly for enterprises.

[4][5] The business type and scope is same as Itochu Techno-Solutions, SCSK and Uniadex, these are also the companies in Japan and mostly for enterprises.

[6] In January 2015, The company became the wholly owned subsidiary of Mitsui & Co. by takeover, and was delisted on Tokyo Stock Exchange.