A novel design of a circular polarized antenna for multiband GPS receivers is presented. The design employs the concept of multistacked patches fed through a single coaxial probe. Three patches being stacked together with a slit and symmetry I-slot are used to achieve triple operating frequency bands for GPS including L1 (1.575 GHz), L2 (1.227 GHz) and L5 (1.176 GHz). The proposed antenna has achieved a bandwidth of 2.0%, 1.5%, and 1.7% at GPS L1, L2, and L5 bands, respectively. It exhibits a minimum axial ratio of 0.51 dB with broad beamwidth in the upper hemisphere required for the GPS applications. The design of the proposed antenna is verified in the experiment. In addition, a detailed analysis has been carried out to study the effects of different geometrical parameters on the performance of the antenna.