Cymmer is located in the lower Rhondda Valley about halfway between Treorchy and Pontypridd. It is situated on the A4119 road half a mile from its junction with the A4058 road.
Cymmer is situated in the Rhondda Valley's lower area, roughly equidistant from Treorchy and Pontypridd. It is connected to the surrounding roads, specifically the A4119 and A4058 routes.