The utility model relates to an outdoor high-voltage falling type fuse which comprises a main fuse, a subsidiary fuse of which the circuit is connected with a circuit of the main fuse in parallel, and a switching mechanism which is connected between the main fuse and the subsidiary fuse and can reclose when a main fuse carrier falls. When the utility model is under a normal operating condition, the main fuse is switched on and is under an operating condition, the switching mechanism is switched off, and the subsidiary fuse is under a back-up condition. When a system is out of action, the main fuse breaks, and the switching mechanism is switched on, and the subsidiary fuse is switched on and is under an operating condition. At this time, if the system failure is temporary, the subsidiary fuse continues to work until a loop is switched to the running status of the main fuse again; if the system failure is permanent, the subsidiary fuse breaks again; at this time, the system stops running. The utility model can provide the most elementary one-time coincidence function for an overhead line in 10KV through simple structure and low cost; as a consequence, the utility model reduces deciduous power-off accidents and assures the running quality of overhead distribution networks.