In view of positioning accuracy and dynamic demanded by receiver, second-order frequency-locked loop with third-order phase-locked loop algorithm was analyzed. First, different frequency discriminator algorithms and different phase discriminator algorithms were analyzed and simulated. Based on this, the frequency discriminator algorithms and phase discriminator algorithms to be adopted were determined. Then the second-order frequency-locked loop structure and the third-order phase-locked loop structure were given. The performances of the second-order frequency-locked loop, the third-order phase-locked loop and the second-order frequency-locked loop with third-order phase-locked loop were simulated. The simulation results show that the second-order frequency-locked loop with third-order phase-locked loop gives full play FLL and PLL advantages and avoids its disadvantages. It can achieve higher dynamic and higher tracking accuracy at the same time.