Prime Minister of the
Kingdom of Westralia
Western Australian Coat of Arms
John Forrest.jpg
Harold Symons

since 2nd July 1875
Style The Right Honourable
Residence Alexander Hall, Perth
Term length Five year term, renewable once
Inaugural holder Frederick Mayweather
Formation 1 August 1869
Deputy Deputy Prime Minister

The Prime Minister of the Kingdom of Westralia is the head of His Majesty's Federal Government in Westralia. The Prime Minister (informal abbreviation: PM) and Cabinet (consisting of all the most senior ministers, who are government department heads) are collectively accountable for their policies and actions to the Monarch, to Congress, to their political party and ultimately to the electorate. The current Prime Minister, Harold Symons, a member of the Democratic Labour Party, was appointed by the King and inaugurated on 2 July 1875.

The office is established by the Westralian Constitution, which stipulates that the monarch must appoint as prime minister the person elected to the office by the people in a Federal Ministerial Election, the two candidates to which are chosen by the two largest parties in Congress. The Prime Minister is primus inter pares or the first among equals in the Cabinet and the head of government in Westralia. Certain privileges, such as residency of Alexander Hall, are accorded to the Prime Minister by virtue of his position.