The invention discloses a mountain fire monitoring and positioning method based on a small-sized radar. According to the mountain fire monitoring and positioning method based on the small-sized radar, the Doppler radar is used for performing stereoscopic scanning within an appointed region, a suspected fire point meeting the mountain fire echo feature can be found by analyzing the basic reflectivity and the radial speed; the fire point is confirmed according to a result of an infrared sensor, so that mountain fire monitoring and positioning for a power transmission line are realized. The mountain fire monitoring and positioning method based on the small-sized radar well solves the problem that the Doppler radar cannot effectively distinguish fire echo and precipitation echo with low intensity during fire condition monitoring and the problem that the infrared sensor is relatively low in space resolution by combining a Doppler radar stereoscopic scanning result and an infrared sensor result.