A microstrip antenna positioned on a substrate includes a feeding portion, a grounding portion, and a radiating portion. The substrate includes a first surface and a second surface opposite to the first surface. The feeding portion is positioned on the first surface. The grounding portion is positioned on the second surface. The radiating portion is positioned on the first surface, and includes a first radiator, a second radiator in zigzag shape, and a third radiator. The first radiator includes a first radiating section and a second radiating section. The third radiator includes a third radiating section and a fourth radiating section. The first radiating section, the second radiating section, the second radiator, the third radiating section, and the fourth radiating section are perpendicular to one another connected one by one in sequence. The first radiator and the third radiator co-define a receiving area, and the second radiator is positioned in the receiving area.