Various sensors in flight control system play a vital role in stability and control of the aircraft,and are critical for the safety of aircraft.The conventional redundancy method has the characteristics of “high safety and low cost-efficiency”.Improving the safety of the system through redundancy design has brought some problems on the aircraft weight and structural design,system integration,maintenance and inspection costs.Aiming at various sensor failures in civil aircraft flight control systems,the typical failure mode is introduced,as well as the design considerations on failure tolerance.The research and application of model based methods and information based methods in related fields are elaborated.Finally,the present challenges and future developments of sensor fault diagnosis are analyzed,and the great potential of advanced fault diagnosis methods in aircraft flight control systems is clarified.