A multi-band inverted-F antenna including a ground plane, a signal feeding circuit, first, second and third main radiation parts is provided. The signal feeding circuit is electrically isolated from the ground plane and receives/transmits wireless signals. The first and the second main radiation part are both physically and electrically connected to the signal feeding circuit, and generate first and second frequency band operation modes for the inverted-F antenna, respectively. The third main radiation part is electrically isolated from the signal feeding circuit, the first and the second main radiation parts, and generates a third frequency band operation mode for the inverted-F antenna via to signal coupling between the first and the third main radiation parts and/or signal coupling between the second and the third main radiation parts.