Portable electronic device and plate antenna module thereof

A portable electronic device and a plate antenna module thereof are provided. The plate antenna module includes an antenna carrying structure, an inner surrounding radiation structure, a first inner feeding structure, an outer surrounding radiation structure, and a first outer feeding structure. The first inner feeding structure is surrounded by the inner surrounding radiation structure. The inner surrounding radiation structure is surrounded by the outer surrounding radiation structure and separate from the outer surrounding radiation structure. The first outer feeding structure corresponds to the first inner feeding structure. The inner surrounding radiation structure and the first inner feeding structure can cooperate with each other to form a first antenna assembly for generating a first antenna operating frequency, and the outer surrounding radiation structure and the first outer feeding structure can cooperate with each other to form a second antenna assembly for generating a second antenna operating frequency.