This paper describes a GNSS simulator signal generation method based on GPU acceleration. Mathematical simulations of the satellite constellation and receiver carriers enable simulation control software (SCS) to periodically send the parameters of the visible satellites to users. Furthermore, the SCS calculates simulated digital IF signals by calling multiple parallel threads on the GPU. To improve the parallel computing speed, the data structure is designed to facilitate quick access to the pseudocode data. We propose an optimal CUDA implementation for calculating the sampling data according to the characteristics of the GNSS signals. Simulations demonstrate the effectiveness of the proposed method.