Portable electronic device and antenna module thereof

A portable electronic device and an antenna module thereof are provided. The antenna module includes a first substrate, a chip antenna and a second substrate. The first substrate has a conductive wire electrically connected to a resonant circuit of a system module. The chip antenna is disposed on the first substrate and electrically connected to the conductive wire. The second substrate and the first substrate are separate from each other in a predetermined distance, and the chip antenna is below the second substrate. The chip antenna and the conductive wire form a circuit, and the circuit is insulated from and not connected to the second substrate. This is to make the circuit provide a magnetic field with a predetermined frequency by matching the resonant circuit, and make the magnetic field radiate to the second substrate thereby generating near field communication signals.