Gan made her political debut in the 2020 general election when she contested as a PAP candidate in Marymount SMC and won with 55.04% of the vote against Progress Singapore Party's Ang Yong Guan.

[5][6] Gan started her career as a weapon systems officer in the Republic of Singapore Air Force.

[9][10] In a speech at a Convention on the Elimination of All Forms of Discrimination Against Women forum held on 3 October 2015, Low Yen Ling cited Gan as "one notable example who smashed the 'brass ceiling' to become the first female general in the Singapore Armed Forces".

On 26 June 2020, Gan was officially introduced as a People's Action Party (PAP) candidate contesting in the 2020 general election.

Gan is married to Lee Jek Suen, a former Republic of Singapore Navy officer who now works at Jurong Port.