The invention discloses a system and a method for real-time unmanned plane flight state evaluation early warning. The system comprises an evaluation early warning platform, an unmanned plane and a ground monitoring station, wherein the ground monitoring station is used for monitoring the flight state data of the unmanned plane and transmitting the data to the evaluation early warning platform, the evaluation early warning platform is used for reading the flight state information and flight control data of the unmanned plane, through the flight control data of the unmanned plane accumulated at each inspection, an unmanned plane flight state evaluation model is constructed, the flight state of the unmanned plane is determined, a flight instruction transmitted by a host computer is further received, and flight of the unmanned plane is adjusted. According to the method, the flight control data of the unmanned plane can be inspected through a power transmission line, through the combined time sequence analysis, clustering analysis and supporting vector machine analysis method, the flight state evaluation early warning model is constructed, and real-time flight state evaluation early warning of the unmanned plane in the power transmission line inspection process can be realized.