MRWA G class
|Midland Railway of Western Australia G class|
G51 at Northcliffe in July 1986
|Builder||English Electric, Rocklea|
|Gauge||1,067 mm (3 ft 6 in)|
|Prime mover||English Electric 8SVT|
|Engine type||Four-stroke diesel|
|Generator||English Electric 819 7E|
|Traction motors||English Electric 548A|
|Power output||1,000 hp (750 kW)|
|Operator(s)||Midland Railway of Western Australia|
|Number in class||2|
|First run||7 May 1963|
|Disposition||1 preserved, 1 scrapped|
The G class were a class of diesel locomotives built by English Electric, Rocklea for the Midland Railway of Western Australia in 1963. They were later sold to the Western Australian Government Railways.
The G class was a class of diesel-electric locomotives based upon the British Rail Class 20. The two members of the class entered service with the Midland Railway of Western Australia in May 1963 after being shipped from Rocklea. They entered service on the Midland to Watheroo line. 
Together with the rest of the company's assets and operations, they were taken over by the Western Australian Government Railways in 1964. In their later years they operated out of Bunbury and Perth.
G51 was withdrawn from service in May 1990, and scrapped in January 1991.
- Gunzburg, Adrian (1968). WAGR Locomotives 1940–1968. Perth: Australian Railway Historical Society (Western Australian Division). pp. 34, 48. OCLC 219836193.
- Gunzburg, Adrian (1989). The Midland Railway Company Locomotives of Western Australia. Melbourne: Light Railway Research Society of Australia. ISBN 0909340277.
- Milne, Rod (1998). Westrail's English Electric Experience (The English Electric locomotives of the WAGR). Elizabeth, SA: Railmac Publications. ISBN 0958650098.
- "Midland's New Medium Powered Diesels (G-Class)". Railway Transportation (Surry Hills, NSW: Shennen Publishing & Publicity Co). ISSN 0033-9024. OCLC 220305870. Media related to MRWA G class at Wikimedia Commons