In this paper, a novel miniaturized circularly polarized (CP) antenna for BeiDou Satellite Navigation System (BDS) applications is presented. The proposed antenna is composed of three substrates with the same size, which are combined by four shorting pins. Parasitic strips are used to reduce the size, and the radiation patch is fed by two coupling feeding patches with the same amplitude and 90° phase difference. The overall dimension of the proposed antenna is only 18 mm x 18 mm x 23.5 mm (about 0.08λ0 x 0.08λ0 x 0.1λ0), and its weight is about 25 grams. The performance study with different geometric parameters has been conducted. A prototype based on optimized dimensions has been fabricated and measured, and the tested results exhibit a good impedance matching bandwidth ranging from 1.2 to 1.35 GHz centered at 1.268 GHz. This antenna also has stable hemispherical radiation patterns and good CP characteristics. Good agreement between analytical and experimental results is obtained.