John Willcock Labor John Willcock Labor Elections were held in the state of Western Australia on 18 March 1939 to elect all 50 members to the Legislative Assembly.

The Labor Party, led by Premier John Willcock, won a third term in office against the Country and Nationalist parties, led by Opposition Leader Charles Latham and Robert Ross McDonald respectively.

This was the first election in Western Australia since the enactment of compulsory voting, which occurred in 1936.

Only one member—former Speaker Michael Troy, who had been in the Assembly continuously since 1904—opted to retire, being replaced in his seat of Mount Magnet by fellow Labor member Lucien Triat.

Elsewhere, the only change was the exit of one Independent member—Clarence Doust in Nelson, who was defeated by his Nationalist predecessor John Henry Smith after one term—and the entry of another from Irwin-Moore, Claude Barker, replacing Country member Percy Ferguson.