The utility model discloses a drop-out fuse with a stable structure. The drop-out fuse comprises a porcelain insulator, a fuse tube and an upper support frame and a lower support frame which are respectively fixed to two ends of the porcelain insulator. A connection support is fixed to the upper support frame. One end of the fuse tube is movably connected with the lower support frame and the other end successively passes through a second fuse wire, a resistor and a first fuse wire to be connected with the connection support. A ratchet mechanism is fixed to the lower support frame. A drive swing rod of the ratchet mechanism is fixed to the fuse tube. Two ends of the resistor are connected to a fusing alarm device. The drop-out fuse has advantages as follows: the structure of the drop-out fuse is stable; the fuse tube will not rebound after falling off and the structure is simple; and the drop-out fuse has a fusing alarm function such that it is convenient for maintenance personnel to judge a fusing branch.