Lau was the third child of Lau Cham (Lau Jaam, 劉湛), a martial arts master who studied Hung Gar under Lam Sai-wing, a student of Wong Fei-hung. He has a brother who makes a living in the film industry, actor/choreographer Lau Kar-wing, as does Gordon Liu, Lau's pupil and adopted godson to Lau's father, Lau Cham. His nephew Lau Kar-Yung (son of his older sister) is also an actor, choreographer and director. Another nephew, Lau Wing-kin (Lau Kar-wing's son) is also an actor, and assisted Lau Kar-leung with action-directing "Seven Swords"