To provide an explosion cutoff device in a simple structure and a flying object using the same, which simultaneously cuts a plurality of objects to be cut for a reduction in the whole weight of a device.

This explosion cutoff device has a molded blasting cable 10 including a liner 11 filled with an explosive 12, and a detonator connected with the shaped blasting cable 10, and the liner 11 is formed with a plurality of grooves 13 respectively opposed to the plurality of cut objects 30.