The invention discloses an evaluation method for an electric transmission line orientated forest fire approaching risk. The method includes the following steps that A, forest fire happening information is obtained from a forest fire monitoring system based on satellites; B, electric transmission lines affected by ignition points are determined according to the happening position of the ignition points and longitude and latitude coordinates of the electric transmission lines; C, real-time meteorological data are obtained from an automatic meteorological monitoring station; D, according to the forest fire happening information, the real-time meteorological data and the electric transmission lines affected by the ignition points, risk indexes of the forest fire on all the electric transmission lines affected by the ignition points are sequentially calculated; E, a forest fire early warning risk grade of the forest fire event is determined according to the forest fire approaching risk indexes, and forest fire approaching risk early warning information is issued according to a set issuing standard; F, whether risk evaluation calculation is completed or not is judged. The evaluation method can quickly evaluate the risks of the forest fire on nearby lines after the forest fire happens, and the early warning information can be issued according to an evaluation result.