Kai may refer to:

• Caleb Lawrence McGillvary, a hitchhiker who goes by the name of Kai
• Kai (name), including lists of those with the surname or given name
• Kai or Kayi tribe, a Turkish tribe to which the ruling family of the Ottoman Empire
• Kai (wrestler), Japanese professional wrestler Atsushi Sakai
• Kai Winding, Danish-born American trombonist and jazz composer
• Kai (singer), Kim Jong In, one of the members of K-Pop group EXO
• Kai (Alessia De Gasperis Brigante), pop singer/songwriter from Toronto, Ontario
• Kai Greene, American IFBB professional bodybuilder

(also known as 改-KAI- REMIX01) is a remix album released by Dir En Grey on August 22, 2001. It features remixes of songs from the band's first two studio albums, Gauze and Macabre, as well as the Ain't Afraid to Die single. The songs were remixed not only by outside musicians, but also by members of the Dir en Grey themselves. Five of the album's tracks had been previously released as B-sides on various singles.