Compared with a single train positioning method，integrated navigation technology can effectively improve the performance of train positioning systems. This paper introduces the basic principle of the integrated navigation technology of strapdown inertial navigation system（SINS）/satellite navigation （GNSS） for trains，and proposes a practical Kalman filtering algorithm for loose integrated of inertial navigation and satellite navigation. By utilizing the technical advantages of inertial navigation and satellite navigation，it overcomes the adverse effects of geographical and environmental factors on train travel routes and continuously provides accurate positioning information for trains. By analyzing the actual travel data of complex routes，the accuracy of integrated navigation positioning meets the requirements. The practicability and effectiveness of the integrated navigation algorithm are verified，which ensures the safety of train operation and transportation efficiency.