The utility model relates to an outdoor AC high-voltage drop-out fuse. The fuse comprises an insulator and a fuse tube. Two ends of the insulator are provided with an upper electrode and a lower electrode. The upper electrode comprises an upper electrode connecting plate installed at one end of the insulator, a static contact piece electrically connected with the upper electrode connecting plate,a rain shielding cover arranged above the static contact piece and a spring arranged between the static contact piece and the rain shielding cover. The upper end of the fuse tube is electrically connected with the static contact piece, and the lower end of the fuse tube is hung on the lower electrode and electrically connected with the lower electrode. A constraint cap and a columnar body for limiting the expansion amount of the spring are arranged between the rain cover and the static contact piece; one end of the constraint cap is provided with a positioning hole, and the other end is arranged on the rain cover; a constraint space is defined by the constraint cap and the rain shielding cover, the columnar body is installed on the side, making contact with the spring, of the static contact piece and penetrates through the spring and a positioning hole in the constraint cap to extend into the constraint space, electrical connection between the static contact piece and the fuse tube canbe rapidly disconnected at the moment when the fuse is fused, a circuit is cut off, and the service life is prolonged.