To improve the reliability, real-time performance and maintainability of navigation system, an optical-mechanical-electrical integrative design method of the fiber optic gyro inertial navigation /beidou/odometer integrated navigation system is proposed. Based on the basic working principle of the integrated navigation system, design of system structure and signal connection are implemented. In the integrated navigation system, all-fixed-structure, instrument and system integrative design and modularization design are used. At last, the integrated navigation system is developed, north seeking test and vehicle test are carried out to demonstrate the validity of the referred system design.