Ang Mong Seng PBM, BBM (Chinese: 洪茂诚; pinyin: Hóng Màochéng; born 30 September 1949) is a Malaysia-born Singaporean former politician.
By 1988 he had worked his way up the ranks to become General Manager of Bukit Panjang and later Sembawang Town Councils.
In the 2001 general elections, the PAP defeated the Singapore Democratic Party with 79.74% of the votes for Hong Kah GRC.
Prior to his stint in Hong Kah GRC, Ang represented Bukit Gombak SMC from 1997 to 2001 where he defeated Ling How Doong from Singapore Democratic Party and a third candidate from the Singapore People's Party in the 1997 general elections.
Ang retired from politics prior to the 2011 general elections, and Bukit Gombak ward was absorbed into the newly created Chua Chu Kang GRC while Hong Kah GRC was dissolved.