A pipe joint construction comprising an elastic seal member (4) for hermetically sealing between an inner circumferential surface of a receiving pipe section (1) and an outer circumferential surface of an inserted pipe section (2) inserted into and connected to the receiving pipe section in a pipe axis direction (X), and a lock member (7) provided in the inner circumferential surface of the receiving pipe section (1) adjacent a receiving opening thereof for preventing separation of the pipe sections by contacting an engaging projection (5) protruding from the outer circumferential surface of the inserted pipe section (2) in the pipe axis direction, wherein the construction further comprises an attachment/detachment control device (A) for attaching and detaching the lock member (7) to/from the receiving pipe section (1) by rotating the lock member (7) about the pipe axis direction (X) relative to the receiving pipe section (1) and by moving, in the pipe axis direction (X), the lock member (7) placed in a specific position in a passage of rotation.