Abstract: Aiming at the problem that the reliability of the low-cost embedded integrated navigation system is easily affected by various sensor failures and environment, a two-level fault detection and processing method is proposed based on inertial navigation system/GNSS/Odometer (INS/GNSS/ODO) robust integrated navigation algorithm with multiple Global navigation satellite system(GNSS)states. The first level detection uses the residual chi square test method based on analytic redundancy, and the second level test uses the improved dual state propagation chi square test algorithm use the self-developed GN310 low-cost embedded system to collect drive test data. The results show that the horizontal positioning accuracy is improved by 39.7% compared with the traditional algorithm. In addition, in the hardware in the loop simulation, the horizontal positioning error is kept within 3 m, which shows that the fault-tolerant method can effectively deal with ODO, mechanical arrangement fault and GNSS soft fault.