He was a Country Party member of the New South Wales Legislative Assembly from 1932 to 1941, representing the electorate of Castlereagh.
[1] Yeo entered state politics at the 1932 election, when he was preselected as the Country Party candidate for the Labor-held seat of Castlereagh, held by Joseph Clark.
[2] He held the seat in 1932 and 1938, and became Country Party Whip before being appointed Secretary for Lands on 6 November 1940, only seven months before the 1941 state election.
[3][4] The electoral redistribution before the 1941 election weakened Yeo's margin in Castlereagh, and he chose to contest the open seat of Liverpool Plains that year.
[8] He subsequently retired from elective politics, but continued to serve on the state council of the Country Party until 1946.