The current applications of railway inspection unmanned aerial vehicles(UAVs)in China and United States,Korea,Australia,and the Netherlands are elaborated.The advantages of using UAVs in railway inspection are concluded.Railway inspection UAVs have problems with restricted flight rights,lack of flight operators,low level of intelligent processing of results and constraints by bad weather.The future development direction is proposed in terms of the degree of automation,recognition in the railway industry,scope of application,the integration of inspection data,handling of foreign objects on the catenary and operation management.