In order to improve the anti-noise property of grid algorithm, an identification algorithm based on back propagation (BP) network was proposed. It extracts the number of rows and columns to form matching vector by transfroming the star pattern into a grid matrix of "0", "1" and "2". Then multiple BP recognition subnets were used for training to complete the matching recognition. Simulation results indicate that, when the standard deviation of position noise is 2 pixels, the recognition rate and the recognition time of BP network algorithm is improved by 2% and 60ms compared to grid algorithm after adding noise to both star locations and star magnitude. This algorithm based on BP shows strong anti-noise ability and faster identification speed.