PROBLEM TO BE SOLVED: To provide a spray adaptor of an endoscope capable of washing away mucus firmly stuck to an observation window by attaching a spray function optionally as need arises, even when a general endoscope adopting no function of forming a spray state in a water feed operation is used.SOLUTION: A spray adopter 30 that is detachably and interposedly connected between an air/water feed connector 20 and an air/water feed connector receiver 10 is provided for an air/water feed device of an endoscope. The spray adopter 30 includes a spray vent passage 39 that causes pressurized air fed through an air feed pipe 21 to flow in connector parts 31 and 32 between a water feed pipe 22 and a water pipe, mixes it with water passing through the water feed pipe 22, and feeding the mixture to the water pipe. This configuration can form the water to be sprayed to the observation window into an air-mixed spray state.
