The invention discloses a flight plan evaluating system and implementation method applicable for general aviation. The system comprises a microcomputer and at least one database server. The database server is connected with the microcomputer through a digital network. The system has the advantages that factors such as the terrain, the plane type, aviator aptitudes, stowage, fuel oil, taking-off and obstacle crossing, no-fly zones, airports and air line periphery meteorological conditions which affect general aviation flights are mainly analyzed, factors which slightly affect general aviation flight are simplified, and distinctive general aviation features are achieved; a three-dimensional geographic model is built by means of a terrain data repository, the three-dimensional space position is calculated based on the longitude and latitude coordinates of each flight path point and cruise altitude information in the flight plan, and three-dimensional evaluation is achieved for the general aviation flight plan flight path by combining the terrain, the control zone, the monitoring zone, the report zone, the no-fly zone, the abnormal weather zone and other information of the three-dimensional space where the flight path is located.