 Initially a member of the United Sabah Party (PBS), Dompok contested, and won, both the Sabah State Legislative Assembly seat of Moyog, and the federal seat of Penampang, in separate 1986 elections.PBS won a majority in the state assembly at the election, and Dompok was appointed the state's finance minister.He became the President of the UPKO, then known as the Sabah Democratic Party (SDP), in 1994.