A voice coil motor includes a stationary member and a moveable member. The stationary member defines a central axis. The stationary member includes a first receiving room, four sidewalls surrounding the first receiving room and four guide rails formed on the respective sidewalls and located in the receiving room. The moveable member is received in the stationary frame. The moveable member includes a moveable frame. The moveable frame includes four side surfaces. A plurality of restricting posts extend from each side surface and are aligned in a line parallel to the corresponding guide rail. The restricting posts slidably engage in the corresponding guide rails.