Kang was born in Clarkston, Georgia, to South Korean immigrant parents before moving to Gainesville, Georgia. He was raised by his Korean mother and African American stepfather. He moved to Barstow, California while in high school.
Kang attended the University of California, Riverside. While in college he chose acting over law school, a decision which was met with disappointment from his parents due to their concerns over the lack of Asians on American television and lack of job prospects.
Kang's first major role was as Han Lue in the Fast & Furious franchise, a character he first portrayed in Better Luck Tomorrow (2002). Kang also played John Mak in the television series Power.