Sun started her career in the
Economic Development Board (EDB) in 2003 before she joined
DBS Bank as an Assistant Vice President. She was Director of Investment Groups at
Temasek Holdings and had spent eight years based in Hong Kong and China working for
Deutsche Bank AG as a Director and later
Macquarie Securities as a Senior Vice President. She was also Chief Executive Officer of Business China from 1 November 2015 to 20 May 2018.
Political career Sun was introduced by the
People's Action Party (PAP) as a candidate contesting in
Pasir Ris–Punggol GRC on 1 August 2015 in the lead-up to the
2015 general election. Before her candidacy was announced, she had been active in grassroots activities in
Buona Vista since 2001 and had been advocating women's and mothers' rights. During the campaigning period for the 2015 general election, Sun was the target of xenophobic comments online because her name in
hanyu pinyin misled people into thinking that she was a Chinese national. On 1 May 2018, Sun was appointed
Senior Parliamentary Secretary at the
Ministry of Home Affairs and
Ministry of National Development. She won with 60.98% of the vote against Tan Chen Chen from the
Workers' Party (WP). On 27 July 2020, she was promoted to
Minister of State and appointed to the
Ministry of Social and Family Development and
Ministry of Education. On 13 June 2022, Sun was appointed Minister of State at the Ministry of Home Affairs and relinquished the Education portfolio. In 2025, Sun contested in the new Punggol GRC after it was created by merging Punggol West SMC with the Punggol section of Pasir Ris–Punggol GRC as part of a four-member PAP team. The PAP proceeded to defeat the WP with 55.17% of the vote. ==Personal life==