- Name: 徐子淇 / Tsui Chi Kei (Xu Zi Qi)
- English name: Cathy Tsui
- Profession: Model and actress
- Birthdate: 1982-Nov-29 (age 34)
- Birthplace: Hong Kong
- Nationality: Australian
- Height: 169cm
- Weight: 49kg
- Star sign: Sagittarius
- Chinese zodiac: Dog
- Family: Parents, sister, husband/billionaire heir Martin Lee (李家誠), daughter Leanna Lee (李晞彤) (b. 2007-Jul-17), daughter Hayley Lee (李晞兒) (b. 2009-May-16), son Triston Lee (李俊熹) (b. 2011-Jun-21), son Preston Lee (李建熹) (b. 2015-Oct-01), and father-in-law/billionaire Lee Shau Kee (李兆基)
- Education: University College of London (Eastern European Economics and Commerce)
- Languages spoken: English, Cantonese, and Mandarin
- She was born in Hong Kong, but grew up in Australia.
- She married wealthy businessman Lee Ka Sing on December 15th, 2006 in Sydney, Australia.