Dinninup is a small town in the South West region of Western Australia. It is between Boyup Brook and Kojonup.

The town's name is Aboriginal in origin and is the name of a brook that is situated close to town. The name was first recorded by surveyors in 1877; the meaning is unknown. Originating as a railway station on the Boyup Brook to Kojonup line, the land was requested by early settlers to be set aside for a townsite in 1906. The line was completed in 1910 and the Dinninup station was opened at the same time. The town was gazetted in 1915.