Gary Tan Lee Yu (born 21 April 1982) is a Singaporean and former national swimmer.

On 18 June 2001 at the SEA Games Time Trials in the 200 Meters Backstroke he came in at 2:05.07 which is a record in Singapore.

On 7 December 2003 at the 22nd SEA Games in Hanoi, Vietnam, Gary won the bronze medal in the Men 200 Meters Medley with the time of 2:05.94 which is a record in Singapore.

He was also the head coach of the Phoenix Swim Team, which represents UWCSEA (United World College of South East Asia) Dover.

[citation needed] In 2011, Tan was suspended for a year for consideration for national coach accreditation after assisting a swimmer, Jeffrey Su, from Swimfast Aquatic Club to be absent without official leave when Su was supposed to be at Singapore Sports Council's physiotherapy and recovery sessions.