Abstract: In a fluid coupling a bellows holder (21) and a shower ring (25) are axially movably mounted in a housing (15, 16, 17, and 18); the holder (21) supports a bellows (22); the shower ring (25) is fixedly mounted in the holder (21); the bellows (22) has a valve (39) in its front end; the valve (39) is disposed in the shower ring (25); the shower ring (25) has a cleaning chamber (25a) which is round in cross section to receive therein a plug (6) being coupled; the plug (6) has a valve (31) corresponding to that of valve (39) of the bellows holder (22); an O-ring 47 is disposed in an intermediate portion of the chamber (25a) which has an injection spout (46) in its side wall; a nozzle (43) is disposed in wall portion of the housing (15, 16, 17, and 18) and the housing (15, 16, 17, and 18) having a drain (50) disposed therein; the nozzle (43) supplies wash water to a spout (46) in shower ring (25); whereby, a strong current of wash water is introduced into the cleaning chamber (25a) and about an outer peripheral sur