A receptacle module for detachably connecting a connector of a distal end device coming into contact with or inserted into a subject includes: a receptacle substrate including a first surface on which a receptacle to which the connector is detachably connected is mounted, and a second surface on an opposite side of the first surface； a patient circuit unit conducted to the distal end device via the receptacle； and a conductive shielding member mounted on the second surface and configured to shield the patient circuit unit from the opposite side.
