Based on the functional characteristics of GNSS navigation system and IMU/ odometer navigation system, the simulation platform of vehicle GNSS+IMU/ odometer integrated navigation system is constructed. Because the integrated navigation system simulation platform has the characteristics of expansibility, reconfiguration, display interaction, fault tolerance, etc., it can realize the corresponding functions of mode selection, navigation data loading, trajectory simulation, result display, operation, exit, etc. The real data were collected and loaded into the system simulation platform through the test, and it was found that the data measured by the IMU/odometer and the GNSS navigation system were in good agreement. When the vehicle travels to the overpass, overpass or cave, the GNSS antenna's ability to receive signals becomes weak or in a state of no signal, and the IMU/ odometer system is not affected, which just makes up for the defects of the GNSS system, and realizes the accuracy and stability requirements of the GNSS+IMU/odometer integrated navigation and positioning system.