She's starred in over 100 movies. Since 2005 her films have earned over HK$700 million at the box office. She is the Asia Advisor at the British Academy of Film and Television Arts (BAFTA). And once, three ghosts peed on her (Vampire Kids, 1991). She is Sandra Ng, the Queen of Comedy and one of the most beloved actresses in the world.

Willing to do anything for a laugh, she started out in film while still a teenager, appearing in six hopping vampire movies, dozens of screwball comedies, and action movies like In the Line of Duty III (1988), Operation Pink Squad II (1989), and Thunder Cops II (1989). This last one was a hardcore revenge movie where she turned in a super-serious performance alongside Stephen Chow, also acting very serious. Producers quickly realized that drama was not their greatest strength and soon the two were cast together in Chow's massive comedy blockbuster, All for the Winner (1990). After that, there was no looking back as Ng appeared in comedy after comedy, from God of Gamblers III: Back to Shanghai (1991) and Royal Tramp I & II (1992) with Chow, to Gameboy Kids (1992) and Boys are Easy (1993). Add up her co-stars and you get a gallery of Hong Kong's biggest names: Maggie Cheung, Chow Yun-fat, Andy Lau, Brigitte Lin, and everyone in between.

In 1996, she played four roles in the experimental film 4 Faces of Eve, shot by Wong Kar-wai's longtime collaborator Christopher Doyle, and the following year she appeared in Young and Dangerous 4 (1997) in another dramatic role as the lesbian pimp, Sister 13. Her character's massive popularity led to Sister 13's very own spin-off film, Portland Street Blues (1998), for which she won Best Actress at both the Hong Kong Film Awards and the Hong Kong Film Critics Society Awards. She began to broaden her range, playing a breast cancer survivor in Wilson Yip's Juliet in Love (2000), a mob wife in Dante Lam's moving gangster film, Jiang Hu: The Triad Zone (2002), and providing the voice of Mrs. McDull, mother to Hong Kong's clinically depressed animated piglet, McDull, in five animated McDull movies.

In 2003, she won the Golden Horse Award for Best Actress playing Kum, the unstoppable prostitute in Golden Chicken, and she's gone on to play the same role in both of its two sequels. She portrayed a bisexual woman in Ann Hui's All About Love (2010), which brought her another Best Actress trophy from the Asian Film Festival of Rome, and a humble housewife in Echoes of the Rainbow (2010), which won the Crystal Bear Award at the Berlin International Film Festival and earned Ng a Best Actress nomination at the Hong Kong Film Awards. She's also the producer of the third installment in the popular Golden Chicken series, Golden Chickensss, which took in a whopping HK$43 million at the Hong Kong box office, when it was released For the Chinese New Year, a few months earlier.