The invention discloses an automatic visual observation system and method for pollution flashover of transmission line insulators. A video is made for the leakage current at a target insulator and thepollution flashover event process image of the insulator. Remote view of the pollution state of the surface of a high-voltage line insulator, pollution flashover warning, and video visualization of the evolution process are realized. Therefore, the pollution flashover detection result of transmission line insulators can be obtained more accurately, and the detection quality of pollution flashoverof transmission line insulators is improved.