Cecilia Cheung was born in Hong Kong and educated in Australia. She speaks Cantonese, Mandarin, and English. Her fresh young beauty was discovered after she appeared in a tv soft drink commercial. She was talent-spotted by Chu Wing Lung,who is now her manager. Initially, Cecil's family were reluctant to allow their daughter to enter the entertainment industry, but Chu promised her father that he would take care of Cecil, and ensure that she didn't go astray.

Cecilia made her first film debut in comedian Stephen Chow's 1999 Chinese New Year release King of Comedy. In the film she plays a night club hostess who experiences an unhappy love affair. Cecil herself has said that she is not satisfied with her performance in the film, and hopes that she can do a better job in her next role. She feels that the most memorable shot is one in which she had to cry. It was her most memorable shot because it was hard for her to gather up this kind of emotion. According to Cecil, she had no experience what so ever on which to base her character's attitudes towards men.

After her first movie, Cecil decides to launch her singing career. She releases her first cd called 'Any Weather' in July of 1999. This was the start of a success career as we can see now. Cheung has been linked to Hong Kong male singers such as Daniel Chan and Jordan Chan. She then dated Nicholas Tse in early 2002, but was then dumped by Tse late that year when Tse got back with his ex-girlfriend, singer Faye Wong. Later she was rumored to have dated a younger Lu Siyuan before the relationship ended in 2003. Cheung suffered serious depression and eating disorder after the break up.

Cheung and Tse were first reported to be "getting back together" in early 2006 and on July 31, 2006, Tse officially admitted dating Cheung in an interview with Commercial Radio Hong Kong 881/903.Her career began in 1998, when she was offered to appear in a TV commercial advertising lemon tea. She caught the attention of Stephen Chow after shooting the ad. Later, Cheung made her film debut as a young nightclub hostess in Stephen Chow's The King of Comedy (1999), followed soon after by Fly Me to Polaris (1999).

The latter role earned her the award for Best Newcomer at the Hong Kong Film Awards. In the same year, Cheung launched her singing career with her first Cantopop album Any Weather (1999). For Derek Yee's romantic drama Lost in Time (2003), Cheung won Best Actress at the Hong Kong Film Awards. She played a young woman who lost her fiancé to a traffic accident which left her as a grieving single mother struggling to make ends meet.