To provide a locking body used for coupling a connecting pipe and a pipe to be connected, which has durability against repetition of stress by high hydraulic pressure.

This locking body 1 comprises a projecting portion 2 and locking members 3, 3 at both sides of the projecting portion 2 formed by bending a plate having appropriate elasticity. Each locking member 3 comprises a circular arc portion 31, a horizontally projecting portion 32, a neck portion 32, a skirt portion 34, a bent piece 35 connected with the skirt portion and bent outwardly, a first opening potion 41 and a second opening portion 42. The skirt portion opening the second opening portion 42 forms an edge standing portion 43 on an end potion thereof, thereby increasing strength of the locking member 1 and forming the bent piece 35 at the same time.