Ko Chang may refer to: Ko Chang District, in Trat Province, Thailand's third largest island Ko Chang, Mae Sai, a subdistrict in Chiang Rai Province, Thailand Ko Chang (Ranong), a small island in Ranong Province, Thailand See also Geochang County, also known as Kochang, a county in South Gyeongsang, South Korea USS Mockingbird (AMS-27), also known as ROKS Ko Chang (MSC-521), a YMS-1-class minesweeper of the United States Navy