The First Mitchell Ministry was the 15th Ministry of the Government of Western Australia and was led by Nationalist Premier James Mitchell. It succeeded the Colebatch Ministry on 17 May 1919 after the collapse of Hal Colebatch's brief service as Premier. It assumed a stability which had been absent from Western Australian politics since the 1914 election. The ministry was followed by the Collier Ministry on 15 April 1924 after the Nationalist coalition lost government at the state election held on 22 March.
The following ministers served until the reconstitution of the Ministry on 12 April 1921, following the 1921 state election:
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The following ministers served from their appointment on 12 April 1921 until the end of the Ministry on 15 April 1924, following the 1924 state election:
| Office | Minister | |
|---|---|---|
| Premier Colonial Treasurer Minister for Lands Minister for Repatriation | Sir James Mitchell, MLA | |
| Minister for Education Minister for the North-West Minister for Justice | Hal Colebatch, MLC (until 17 June 1923) | |
| Minister for Education Minister for the North-West Minister for Justice | John Ewing, MLC (from 18 June 1923) | |
| Minister for Works Minister for Water Supply | William George, MLA | |
| Minister for Railways Minister for Mines Minister for Forests Minister for Police Minister for Industries | John Scaddan, MLA | |
| Colonial Secretary Minister for Public Health | Frank Broun, MLA (until 22 August 1922) | |
| Colonial Secretary Minister for Public Health | Richard Sampson, MLA (from 22 August 1922) | |
| Minister for Agriculture | Henry Kennedy Maley, MLA |