Glen Mervyn, Western Australia

Glen Mervyn is a rural locality of the Shire of Donnybrook–Balingup in the South West region of Western Australia. The Preston River and the Donnybrook–Boyup Brook Road run through the centre of the locality from east to west. The Glen Mervyn Dam and reservoir is located on the north-eastern boundary of the locality, with the dam itself being located on the Mumballup side of the border.

Glen Mervyn and the Shire of Donnybrook–Balingup are located on the traditional land of the Wardandi people of the Noongar nation.

Glen Mervyn was once a siding on the Donnybrook–Katanning railway but the railway line ceased operation in 1982. The Glen Mervyn siding, which opened in 1909, was closed in 1975.