The invention concerns a seat tilt apparatus (3) for an electric wheelchair, which wheelchair comprises a chassis (1) and a seat (2). The seat tilt apparatus comprises a base member (11), which is fixable to the chassis and provided with at least one first guide slot (16) a seat supporting member (40) which is arranged to supportably receive the seat, movable in relation to the base member and guided by the first guide slot and a linear drive means (17) which is connected to the base member and to the seat supporting member, for moving the seat supporting member along a motion path, in relation to the base member. The seat supporting member comprises at least one first cam surface (43) facing in a first direction and the base member comprises at least one first rotational support member (31), said first cam surface being arranged to be in supporting contact with said first rotational support member and formed for altering the angle between the seat supporting member and the base member during movement along a first interval of said motion path. The invention also concerns an electric wheelchair provided with such a seat tilt apparatus.
