Design of a compact PIFA antenna on wireless multimedia devices is proposed in this paper. This PIFA antenna with L-shaped radiator is fabricated using a 0.2 mm thick FR4 substrate, and the antenna's radiator like a L-shaped structure to meet the omni-directional radiation pattern, which are in accordance with a quarter of the wavelength resonance length for the proposed antenna. In addition, the resonant characteristics and analysis of different lengths and widths of the ground segment are also studied. This experiment simulated the multimedia device to press close to reality. Despite of the volume of the antenna is only 18(W)×18(L)×0.2(H) mm3, the experimental results show that the operating frequency band is available to meet the standard for WLAN 2.4-2.484GHz..