Abstract:Radio frequency is a non-renewable resource, and frequency sharing has become the consensus of the International Telecommunication Union. Multi-service integration has been the development trend of the world radio satellite system. S band 2483.5 MHz ~ 2500 MHz has been allocated into the sharing band of satellite multi-service including radio determinations satellite service, radio navigation satellite service and mobile satellite service by International Telecommunication Union, and is expected to provide four functions: satellite navigation, route tracking, emergency rescue and information relay. The development of S band space based system, the frequency characteristics of navigation communication and the prospect of S band multi-service were introduced, the future application and social and economic benefits of the S band navigation in China were predicted.