Ng enrolled in the TVB acting course in 1981, and then joined the studio upon her graduation. Her coquettish looks often typecast her in supporting roles as mistresses and prostitutes. She left TVB in 1987 and auditioned for Ringo Lam who was looking for a female lead for City On Fire. Ng's acclaimed performance opposite Chow Yun-Fat paved her way to stardom.
Ng was nominated for best actress at the 9th Hong Kong Film Awards for The First Time Is The Last Time, and won kudos at the 30th Golden Horse awards for Remains of a Woman, followed by best supporting actress at the 19th Hong Kong Film Awards for The Kid. She is probably best known in the West for her steamy performance as Princess in Wong Jing's Naked Killer.