embodiment of the present invention referring to fig1 a planar inverted f antenna 1 according to the present invention is made of a metal sheet and comprises a radiating portion 2 a grounding portion 4 and a connecting portion 3 connecting the radiating portion 2 and the grounding portion 4 the radiating portion 2 comprises a first radiating element 21 operating at a lower frequency and a second radiating element 22 operating at a higher frequency and extending along a first direction the first radiating element 21 is of l shape and comprises a first part 210 extending along the first direction and parallel to the second radiating element 22 and a second part 211 extending along a second direction from left end of the first part 210 toward the grounding portion 4 the l shape design of the first radiating element 21 is capable of avoiding adding the lateral size of the planar inverted f antenna 1 the connecting portion 3 comprises a first side section 31 parallel to the second part 211 of the first radiating element 21 and connecting the first radiating element 21 and the second radiating element 22 a second side section 32 extending along the first direction from a lower end of the first side section 31 toward the second part 211 and a third side section 33 extending along the second direction from left end of the second side section 32 to terminate.