The invention discloses an autonomous unmanned-aerial-vehicle patrol method for an alternate current single-circuit tangent tower. The method includes the following steps that S1, key patrol points ofthe alternate current single-circuit tangent tower are determined; S2, key photographing points and key track points are selected in the patrol process, and a patrol route is set; S3, manual inspection is performed according to the set patrol route, and coordinates of the key track points and the key photographing points, the vehicle-head angles of the key photographing points and the angle of acloud platform are collected in the inspection process; S4, according to the data collected in the manual inspection process, an autonomous flight task and an autonomous photographing task of the unmanned aerial vehicle are generated; S5, the generated patrol tasks are uploaded to an unmanned aerial vehicle, according to the task, the unmanned aerial vehicle is controlled to fly automatically, automatically adjusts the heading direction of the vehicle head and the angle of the cloud platform when reaching the key photographing points, triggers a camera to take a picture after adjustment, performs follow-up tasks after photographing, and returns to the take-off point when the tasks are completed. The method has the advantages of low patrol risk, high patrol efficiency and good data consistency.