A wideband circularly polarized reconfigurable microstrip patch antenna fed by L- shaped probes is proposed. The L-shaped probes are connected to a matching network underneath the ground plane, which two polarizations, right hand circular polarization (RHCP) or left hand circular polarization (LHCP), could be excited. With the use of PIN diodes and some biasing/RF components, an electrical switch has been designed. The antenna is capable to radiate either RHCP or LHCP by a single feeding port, with suitable biasing voltage on the switches. Preliminary study found that the antenna attains a bandwidth of about 20% with VSWR<2 and axial ratio<3 dB.