Aiming at the dynamical changes of sensor validity, the asynchronization and time delay of sensors in vehicle multi-sensor integrated navigation system, the INS/GNSS/OD integrated navigation algorithm based on factor graph is proposed. The factor graph model of INS/GNSS/OD integrated navigation system is constructed after the inertial navigation system (INS), global navigation satellite system (GNSS) and odometer (OD) are modeled respectively by the factor graph method. To ensure the realtime performance of the factor graph algorithm, the factor graph is transformed into a Bayes net by the variable elimination algorithm, and the Bayes tree is adopted to implement the incremental inference. The simulation results show that, the integrated navigation algorithm based on factor graph can continuously output high precision navigation results, when the sensor validity changes dynamically, the asynchronization and time delay of sensor measurements exist. It satisfies the requirements of vehicle INS/GNSS/OD system. The factor graph algorithm with strong robustness and flexibility has a great advantage in dealing with multi-sensor information fusion.