A folding mobile phone (folding portable communications device) includes a first housing including a liquid crystal display part (display part) provided at a surface thereof, a second housing including an operating part provided at a surface thereof, and a hinge connecting the first and second housings to allow the first and second housings to be freely opened and closed in their folded form. A cam mechanism (support mechanism) supports the liquid crystal display part switchably between a vertical position and a horizontal position and to allow the liquid crystal display part to turn both clockwise and counterclockwise as viewed from the front.