Abstract: This paper describes the experimental study on gasimpinging jets in a cylindrical cavity filled with water. Measurements ofthe maximum instantaneous pressure in the initiative phase as well as theaveraging and fluctuating pressures in the steady phase indicate that, atthe stagnation point of the impinging region, these three pressures increasewith increasing the nozzle inlet pressure ratio. The obtained results showthat the impinging region, bearing the most intensive dynamic load, is themain noise source. Through a comparative approach, it is found that there isa pressure overshoot phenomenon in the water-filling case and its maximuminstantaneous pressure is much higher than that in the correspondinggas-filling case.