He pursued a civil engineering degree at the California State University in Los Angeles,[4] but did not finish his studies because his father died and he wanted to move back to Hong Kong to be with his mother.

[citation needed] When Cheng was 16 years old, he participated in a singing contest organised by the Hong Kong television network TVB but dropped out halfway because he felt that he was not ready to be a singer at that time.

He returned to Hong Kong and signed a management contract with TVB in the following year and started playing minor roles in some television series produced by the network.

[5] Cheng soared to popularity after portraying "Alan Shum" in the 2006 romantic drama Under the Canopy of Love, for which he also won the TVB Anniversary Award for Best Actor that year.

In 2016, Cheng starred in the drama Blue Veins, in which he played the role of undead human and vampire hunter, Ying Wut-zoek, who had been given super powered immortals during 500 years ago.