A multi-band antenna used in a portable electrical device can work in WWAN and GPS at the same time. The multi-band antenna includes a PCB having a through hole, a first antenna body comprising a first radiating element and a first grounding element formed on a first surface of the PCB, a second antenna body formed on a second surface of the PCB, and a feeding line having an inner conductor electrically connecting to the first radiating element and an outer conductor electrically connecting to the first grounding element. The second antenna body comprises a second radiating element, a second grounding element, and a connecting element connecting the second radiating element and the second grounding element. The first radiating element and the second radiating element electrically connect with each other via the through hole of the PCB.