A multi-band antenna adapted for used in a portable electronic device, includes: a first antenna including a first radiating element, a common grounding element, and a first connecting element connecting the first radiating element and the common grounding element; a second antenna, including a first radiating portion, the common grounding element, and a second connecting element connecting the radiating portion and the grounding element. Free end portions of the first radiating element and the first radiating portion do not align with each other in any direction.