The Colonial Secretary's Office was retitled the Chief Secretary's Department on 16 April 1924. The Chief Secretary's Department was responsible for a number of varied functions including Harbour and Lights, Gaols, Registrar General of Births, Deaths and Marriages, Astronomical Services and Racing.

By 1980, the Department's responsibilities were limited to Prisons, Astronomical Services, Registrar General of Births, Deaths and Marriages and the Correspondence Despatch Office.

The Department was abolished in 1983.

The Chief Secretaries for Western Australia were:

• John Michael Drew: 16 April 1924 - 23 April 1930

• Norbert Keenan, K.C.: 24 April 1930 - 21 september 1931

• Charles Farquharson Baxter: 14 October 1931 - 24 April 1933

• John Michael Drew: 24 April 1933 - 27 August 1936

• William Henry Kitson: 27 August 1946 - 1 April 1947

• Hubert Stanley Wyborn Parker: 1 April 1947 - 6 April 1950

• Victor Doney: 6 April 1950 - 23 February 1953

• Gilbert Fraser: 23 February 1953 - 1 November 1958

• Arthur McAlister Moir: 13 November 1958 - 2 April 1959

• Ross Hutchinson: 2 April 1959 - 16 March 1965

• James Frederick Craig: 16 march 1965 - 3 March 1971

• Robert Henry Claude Stubbs: 3 March 1971 - 8 April 1974

• Matthew Ernest Stephens: 8 April 1974 - 20 May 1975

• Neill McNeill: 5 June 1975 - 10 March 1977

• Sir Desmond Henry O'Neill: 10 March 1977 - 5 March 1980

• William Ralph Boucher Hassell: 5 March 1980 - 19 February 1983

• Joseph Max Berinson: 25 February - 22 April 1983