An arrangement of a connector and a pipe, comprising: a connector main body having a circular opening portion for inserting the pipe having an annular flange portion on an outer peripheral face; a lock member provided in the connector main body and moving between a standby position where the flange portion of the pipe passes through the opening portion, and a connected position where the lock member is moved in a radial direction of the opening portion to allow the pipe to be connected; a lock portion provided in the lock member, and locking the lock member to the connector main body at the standby position; an urging mechanism provided in the lock member, projecting into the opening portion, releasing a locked state of the lock member by the lock portion by being expanded outward when the flange portion abuts at an insertion time of the pipe, and restoring to original state and coming around along an outer peripheral portion of the flange portion thereby moving the lock member into the connected position; and a detection stopper provided in the lock member, and abutting against the flange portion when the locked state is released so as to prevent the lock member from moving into the connected position, and to move into the connected position together with the lock member when the pipe is inserted further and an abutment against the flange portion is released, to thereby be positioned on a side opposite to an insertion direction of the pipe more than the flange portion, and overlapping with the flange portion when the detection stopper is viewed from an axis direction of the pipe, characterized in that, when the pipe is inserted, a tip portion of the detection stopper abuts against the outer peripheral portion of the flange portion of the pipe so as to prevent the lock member from moving into the connected position, and when the tip portion of the detection stopper comes out of the flange portion of the pipe, the detection stopper moves into the connected position together with the lock member. a connector main body having a circular opening portion for inserting the pipe having an annular flange portion on an outer peripheral face; a lock member provided in the connector main body and moving between a standby position where the flange portion of the pipe passes through the opening portion, and a connected position where the lock member is moved in a radial direction of the opening portion to allow the pipe to be connected; a lock portion provided in the lock member, and locking the lock member to the connector main body at the standby position; an urging mechanism provided in the lock member, projecting into the opening portion, releasing a locked state of the lock member by the lock portion by being expanded outward when the flange portion abuts at an insertion time of the pipe, and restoring to original state and coming around along an outer peripheral portion of the flange portion thereby moving the lock member into the connected position; and a detection stopper provided in the lock member, and abutting against the flange portion when the locked state is released so as to prevent the lock member from moving into the connected position, and to move into the connected position together with the lock member when the pipe is inserted further and an abutment against the flange portion is released, to thereby be positioned on a side opposite to an insertion direction of the pipe more than the flange portion, and overlapping with the flange portion when the detection stopper is viewed from an axis direction of the pipe, characterized in that, when the pipe is inserted, a tip portion of the detection stopper abuts against the outer peripheral portion of the flange portion of the pipe so as to prevent the lock member from moving into the connected position, and when the tip portion of the detection stopper comes out of the flange portion of the pipe, the detection stopper moves into the connected position together with the lock member.