Abstract: Cavitation is the important mechanism of high pressure homogenization. Based on fluid dynamics and cavitation theory, correlation of cavitation and jet noise change during high pressure jet homogenizing process were analyzed and estimated to evaluate cavitation. Experimental investigation of cavitation and jet noise was carried out by using different ratio ethyl alcohol-water mixture solution. Theoretical analysis indicated that cavitation could be strengthened through changing the constitutional ratio of solution. While mole fraction of ethyl alcohol xA in ethyl alcohol-water mixture solution changes from 0 close to 1, cavitation degree during ultra-high pressure jet homogenizing process increased at first and then decreased, and average sound pressure and frequency spectrum of jet noise changed correspondingly. Experimental results are basically consistent with theoretical analysis, so jet noise change can be used to evaluate cavitation conveniently and indirectly.