Lydia Shum nació en 1945 en Shanghái, hija de Sung Shen Gee (沈 賢 祺; 1913-1978 en Shanpei, Ningbo) y Sung Tan Sun (沈 邱 淡 素; 1913-2008). Ella ingresó a la industria del entretenimiento de Hong Kong a la edad de 13 años en 1958, hizo su debut en el cine a partir de 1960, uniéndose a los hermanos "Shaw Brothers", con quienes trabajó como actriz siendo adolescente a la edad de 15 años de edad. En la que tomó algún tiempo para adaptarse en Hong Kong, por diferencias culturales entre Shanghái y Hong Kong, como la gastronomía.

• The Lotus Lamp (1965)
• Three Women in a Factory (1967)
• Broadcast Queen (1967)
• The Iron Lady Against the One-eyed Dragon (1967)
• A Girl's Secret (1967)
• Every Girl a Romantic Dreamer (1967)
• Waste Not Our Youth (1967)
• Unforgettable First Love (1967)
• Lady Songbird (1968)
• Happy Years (1968)
• Four Gentlemanly Flowers (1968)
• A Blundering Detective and a Foolish Thief (1968)
• Won't You Give Me a Kiss? (1968)
• Teenage Love (1968)
• Wonderful Youth (1968)
• We All Enjoy Ourselves Tonight (1968)
• Moments of Glorious Beauty (1969)
• The Little Warrior (1969)
• Teddy Girls (1969)
• To Catch a Cat (1969)
• A Big Mess (1969)
• One Day at a Time (1969)
• Happy Times (1970)
• The Mad Bar (1970)
• The Invincible Eight (1971)
• Songs and Romance Forever (1972)
• The Private Eye (1973)
• Love Is a Four Letter Word (1973)
• If Tomorrow Comes (1973)
• The House of 72 Tenants (1973)
• The Country Bumpkin (1974)
• Tenants of Talkative Street (1974)
• Lovable Mr. Able (1974)
• The Crazy Instructor (1974)
• The Country Bumpkin in Style (1974)
• Kissed by the Wolves (1974)
• Pretty Swindler (1975)
• Don't Call Me Uncle (1975)
• Sup Sap Bup Dup (1975)
• You are Wonderful (1976)[also director]
• Love In Hawaii (1976)
• The Great Man (1977)
• Cat vs. Rat (1982)
• Drunken Tai Chi (1984)
• The Millionaire's Express (1986)
• It's a Mad, Mad, Mad World (1987)
• Mr. Handsome (1987)
• Tiger on the Beat (1988)[cameo]
• Double Fattiness (1988)
• Mother vs. Mother (1988)
• King of Stanley Market (1988)
• Faithfully Yours (1988)
• It's a Mad, Mad, Mad World II (1988)
• The Bachelor's Swan-Song (1989)
• City Squeeze (1989)
• Eat a Bowl of Tea (USA 1989)
• It's a Mad, Mad, Mad World III (1989)
• Lost Souls (1989)
• The Banquet (1991)
• The Perfect Match (1991)
• It's a Mad, Mad, Mad World Too (1992)
• The Laughter of Water Margins (1993)
• Perfect Couples (1993)
• He Ain't Heavy, He's My Father (1993)
• Just Married (1995)
• Fitness Tour (1997)
• Happy Together (1997)[2]
• The Stamp of Love (2001)
• Miss Du Shi Niang (2003)
• In-Laws, Out-Laws (2004)
• Where Are They Now? (2006)

• Lydia Sum en Internet Movie Database (en inglés).
• Best Comedy Award