An endoscopic flow-passage confluent structure that connects a gas-feed tube and a liquid-feed tube provided in an endoscope to a confluent tube communicating with an ejection nozzle arranged at a tip of an insertion portion of the endoscope and for ejecting a cleaning fluid toward a viewing window of the endoscope, the structure comprising: (i) a passage connection member having one end opened with two upstream-passage receiving bores in which the gas-feed and liquid-feed tubes are respectively inserted and fixed, other end opened with one downstream-passage receiving bore, and an intermediate region that communicates the upstream-passage receiving bores with downstream-passage receiving bore and comprises a passage confluent space having a diameter increasing in a taper-form in a direction of from the downstream-passage receiving bore toward the upstream-passage receiving bores and (ii) a coupler pipe having one end connected to the downstream-passage receiving bore and other end connected with a base of the confluent tube.
