PROBLEM TO BE SOLVED: To provide a water pipe joint structure not having interference of the water pipe joint and a female member even if the same independently rotate. SOLUTION: The water pipe joint is provided with a universal joint for hose. A sprinkler and other sprinkling facilities can be installed on an external socket. A leak prevention part is provided between the water pipe joint and a female member. The water pipe joint is stopped at a projection part bottom surface of a female member inner hole by a stopping part. The water pipe joint is provided with a male screw or a female screw to fix a cap. A flange of the cap can be fixed on a top part of a projection part of a female member. The water pipe joint and the female member are arranged not to separate. COPYRIGHT: (C)2006,JPO&NCIPI