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. His first major role was in "Better Luck Tomorrow" (2002), in which he played Han Lue, an aloof gang member. He was one of the stars in "The Motel", in which he played Sam Kim. He portrayed Han Seoul-Oh in "The Fast and the Furious" film franchise, appearing in "", "Fast & Furious", "Fast Five", and "Fast & Furious 6", as well as the short film "Los Bandoleros". He also had a role in Jet Li's film "War" (2007), playing an FBI agent, and was featured in the movie "Forbidden Warrior" as Doran, a son of Genghis Khan. He had a small role in the action movie "Live Free or Die Hard", and he appeared in Walter Hill's movie "Bullet to the Head" (2013) as Detective Taylor Kwon, opposite Sylvester Stallone. Kang has had several notable television roles, including the recurring role of the narcissistic President Gin Kew Yun Chun Yew Nee in the Korean drama parody "Tae Do (Attitudes and Feelings, Both Desirable and Sometimes Secretive)" alongside Bobby Lee on "MADtv". He portrayed FBI Agent Tae Kim in the short-lived crime procedural "Gang Related" on FOX. Both roles required him to speak Korean, which he is conversant in. The character Tae Kim was written specifically for him by creator Chris Morgan, who had worked on the "Fast & Furious" film franchise. Kang started the YouTube channel "Sung's Garage" in January 2020, which hosts the videos for the podcast of the same name. Kang credits reporter Jen Yamato of the "Los Angeles Times" and her #JusticeForHan social media campaign for rallying public interest and bringing the character of Han Lue back to the "Fast and the Furious" franchise. Kang reprised his role as Han in "F9" (2021). He owned a restaurant called Saketini in Brentwood, Los Angeles, California, which closed in early 2013. Kang has said that, prior to his casting as Han in "", he had been unaware of the drifting culture that existed in Japan.