In a position adjustable pedal assembly for a vehicle, a pedal pad position is adjustable in a longitudinal direction of the vehicle. A lever is connected to a stationary bracket for a pivotal movement about a pivot axis and is formed with a linear track extending in the vehicular longitudinal direction. A pedal arm is provided with a pedal pad at its lower end and with a guide member at its upper end and is connected to the lever for the pivotal movement with the lever in response to a depression force applied to the pedal pad. An adjust lever is provided on the lever for a relative movement to the lever and is formed with an arc-shaped track. The relative movement of the adjust lever is caused when the guide member moves within the linear track and simultaneously within the arc-shaped track while the pedal pad position is adjusted. The adjust lever is provided with a connecting member which is movable within another arc-shaped track in response to the relative movement of the adjust lever. Accordingly, when the pedal pad position is adjusted to move the guide member, the relative movement of the adjust lever is caused to vary a position of the connecting member corresponding to a magnitude of the movement of the guide member, i.e., corresponding to the variation in a distance from the pivot axis to the pedal pad. The depression force is applied to a vehicle operation system through the connecting member.