An antenna has a ground plane, a radiating member, a signal-feeding member and two grounding supports. The radiating member is suspended over and separated from the ground plane and has two opposite non-radiating edges. Each non-radiating edge has a middle section. Each grounding support is connected perpendicularly to the middle section of one non-radiating edge of the radiating member and the ground plane. The grounding supports connected between the radiating member and the ground plane excellently improve the combination of the radiating member and the ground plane to prevent the antenna from inadvertently disassembling.