The invention relates to a power line safety distance measurement evaluation method based on a smart phone. A smart phone which comprises a camera and a gravity sensing device is provided. Firstly, safety distance measurement software is downloaded and mounted through APP and comprises line and ground vertical distance measurement, line and crossing span substance vertical distance measurement, line and tree distance measurement, tree cutting security risk evaluation; and then, line and ground vertical distance measurement, line and crossing span substance vertical distance measurement, line and tree distance measurement, tree cutting security risk evaluation are all carried out. According to the method, manpower waste is reduced, measurement of all power line safety distances can be realized only through the smart phone, the operation is simple, the implementation is easy and no risk exists in the measurement process.