Various new modulation modes have been introduced into the signals with different frequency bands of Galileo satellite navigation system, which is a typical representative of the new generation satellite navigation system. The limited number of visible Galileo satellites has brought some difficulties to further exploration. In this paper, a Galileo+GPS satellite navigation signal simulator is designed and implemented based on the architecture of "PC+FPGA+DSP". The algorithm of FPGA in satellite navigation signal simulator is mainly studied, doppler frequency shift simulation, subcarrier generation, offset carrier modulation and pseudo range signal generation are completed, key technology of signal alignment of all modules is solved,and the intermediate frequency signals of Galileo E1 OS and GPS L1 C/A are generated. The hardware receiver is used to receive and verify the generated signal, the results of experiments show that the receiver can correctly capture, track and fix positions, and the location coordinates are consistent with the preset coordinates, which prove the correctness of the simulation signal.