Leung was raised in the neighborhoods of Two Bridges and Midwood in Brooklyn, which he recalls fondly. From a young age, he showed a keen interest in both acting and singing. He initially attended a boarding school in New Jersey but eventually transferred to Old Bridge High School, citing discomfort and limited social interaction at his previous school. After graduating, he enrolled at New York University’s Tisch School of the Arts, majoring in Fine Arts. It was during his college years that he committed fully to pursuing a professional acting career.

Career Beginnings and Breakthrough

Ken Leung graduated from NYU’s Tisch School of the Arts in 1995, studying under prominent acting coaches such as Cathy Russell and Nan Smithner. Following graduation, he began auditioning for roles in commercials and television series, gradually building a resume of minor appearances. His first major break came with the 1998 action-comedy film Rush Hour, where he starred alongside Jackie Chan. The film's global success helped showcase Leung’s acting talent to a wider audience.

Shortly after, he gained more visibility with a guest appearance in the long-running television series Law & Order. His role in the 2006 blockbuster X-Men: The Last Stand as Kid Omega further elevated his profile. While some sources mistakenly identify the character as Kid Omega, Leung actually played the mutant character Kid Omega as loosely inspired by the comics' Quentin Quire, though the film never explicitly confirms this.