To provide a jet nozzle having simple constitution and capable of easily adjusting a cavitation effect corresponding to an article to be washed of every kind.

The jet nozzle 10 has a T-shaped trifurcated pipe 1, compressed air piping 2 for introducing compressed air into the trifurcated pipe 1 and a locking member for supporting the compressed air piping 2 on the trifurcated pipe 1. The compressed air piping 2 is supported by the locking member 3 so as to be capable of moving the position of a compressed air jet orifice 2a into the trifurcated pipe 1.