To provide a fuse joint, surely operable, reducing the secular deterioration, post-installable, and usable by being inserted into a conduit for supplying city gas or the like.

When a state of flowing of a flow rate of a specified value or more is caused on the downstream side of a joint body 2, fluid equivalent to an excessive flow rate flows in a flow passage space 6 via a fluid branch hole 11 from the upstream side of an orifice part 7, and this fluid blows up a fuse ball 10 resting in a fluid jetting hole 9 by energy jetting in an inner pipe 5 from the fluid jetting hole 9, and brings the fuse ball into close contact by being made to flow to the ball seat part 8 side, to cut off gas.