The Fourth Deakin Ministry was the eighth Australian Commonwealth ministry, and ran from 2 June 1909 to 29 April 1910.
Commonwealth Liberal Party
- Hon Alfred Deakin, MP: Prime Minister
- Hon Joseph Cook, MP: Minister for Defence
- Rt Hon Sir John Forrest, GCMG MP: Treasurer
- Senator Hon Robert Best : Minister for Trade and Customs
- Hon Littleton Groom , MP: Minister for External Affairs
- Hon Patrick Glynn, MP: Attorney-General
- Hon Sir John Quick , MP: Postmaster-General
- Hon George Fuller , MP: Minister for Home Affairs
- Senator Hon Edward Millen : Vice-President of the Executive Council
- Hon Justin Foxton , MP: Minister without portfolio
