A circularly polarized (CP) wideband annular microstrip patch antenna based on LTCC technology was designed. An annular patch was used for radiant unit in the proposed antenna. The “L” matched stub was used to expand the bandwidth of the antenna.The annular patch was fed by Wilkinson power divider with 90° phase difference, which was used for phase shifting of the perpendicularity electric field and circularly polarized radiation.The profile thickness of the antenna was restricted in 2.4 mm. The simulated results showed that the impedance bandwidth of the antenna exceeded 80 MHz, the axial ratio was less than 1.5 dB and the gain approached to 4.9 dB with the centre frequency of 1.268 GHz. The measured results confirmed the validity of this design.