Connector 41 as the endoscope connector includes an outer tubular member 51, the inner cylinder member 52, a biasing member 53. The outer tubular member 51, inlet port 61 which is the endoscope washing and disinfecting apparatus 1 is connected, the outlet 62, the flow channel P, and the inner peripheral portion 63a provided on the inner periphery of the passage P, from the inner peripheral portion 63a also provided on the outflow port 62 side has a larger inner periphery 63b of the inner diameter than the inner peripheral portion 63a. The inner cylindrical member 52 is disposed so as to be retractable along the flow path P, disposed inner peripheral portion 63b outside diameter small reciprocating portion 52a than the outer periphery and arranged forward and reverse part 52a the inner peripheral portion 63a of the forward and reverse part 52a containing O-ring 54, through passage 65 passing through the forward and reverse part 52a along the flow path P to fill the gap between the forward and reverse part 52a and the inner peripheral portion 63a when it is.
