A gesture recognition method includes determining whether an object stays within a plurality of video frames for more than a specific time; determining a finger number corresponding to the object to generate a finger number determination result, and determining whether or not the object moves away from a light sensing unit to generate an object moving-away determination result, when the object stays within the plurality of video frames for more than the specific time; and determining a gesture of a user according to the finger number determination result and the object moving-away determination result.