To provide a joint capable of being simply mounted and dismounted and a joint structure usable in supplying high pressure water to be supplied to a sprinkler.
This joint 1 is composed of a cylindrical joint main body 2, packing mounting parts 23, 24 formed like recessed shape in the inner wall peripheral direction on both sides in the vicinity of center of the joint main body, and annular packings 3, 4 mounted in the packing mounting parts. The annular packing is composed of an annular basic part 31 abutted on a bottom face of the packing mounting part and an annular abutting part 32 abutted on surfaces of water supply pipes 5, 6 for sprinkling water to be connected by extending the inner side whole periphery of the annular basic part. In this joint structure connected by the joint, a free end fringe of the annular abutting part 32 is arranged toward a central side on an inner wall of the joint main body 2 to seal a section among tips of the water supply pipes 5, 6 for sprinking water and the joint main body.