The invention discloses a low-altitude positioning load air-drop method based on a multi-rotor unmanned aerial vehicle. The multi-rotor unmanned aerial vehicle comprises an aerial flight platform, onboard task equipment and a ground remote control device. The onboard task equipment is located below the aerial flight platform. The onboard task equipment comprises an air-drop engine, a positioning camera and a directional voice broadcast device. The method solves the problem that air-drop of badly-needed emergency supplies is difficult in emergency rescue. The multi-rotor unmanned aerial vehicle has the advantages of being low in cost, easy and convenient to operate and easy to maintain and facilitating transport; with the low-altitude hovering function of the multi-rotor unmanned aerial vehicle and the assistance of the onboard assistant task equipment such as the voice broadcast device and the positioning camera, material air-drop accuracy and utilization efficiency are improved. The method has outstanding application value for a small number of loads which is light and is badly needed by trapped persons, and has great popularization potential in the field of air-drop of emergency rescue supplies.