A wheelchair including a seat body and at least one wheel module disposed at a bottom of the seat body is provided. The wheel module includes a motor, at least one wheel, and a transmission unit coupled between the motor and the wheels. The transmission unit has at least one one-way bearing. The motor supplies a first rotating moment and a second rotating moment to the transmission unit with opposite directions. The one-way bearing transmits one of the first rotating moment and the second rotating moment to the wheel to drive the wheel rolling, such that the seat body is in linear motion, or the wheel module rotates along the directions of the first or the second rotating moments. The axes of the first and the second rotating moments are vertical to the rotating axis of the wheel.
