The process of extraction soy protein isolate from highly denatured soybean meal by alkali lytic acid precipitation method with the aid of jet cavitation was aimed to increase the yield of protein. The effects of different jet cavitation powers（0~2.0MPa）on soy protein isolate extraction rate, secondary structure, oilholding capacity and water holding capacity, solubility, foaming and emulsifying properties were further studied. As the results shown, the free sulfhydryl contents and the surface hydrophobicity of the samples treated by jet cavitation were significantly higher than those of the untreated samples (P<0.05), while the disulfide bond contents were significantly decreased (P<0.05). When the jet cavitation power was 1.5MPa, the extraction rate of soy protein isolate was 58.97%, which was 34.42% more than the untreated sample. The oilholding capacity and water holding capacity, solubility, foaming and emulsifying properties of soy protein isolate were significantly improved. The results indicated that the jet cavitation treatment unfolded the protein molecules, stretched the structure, exposed more free sulfhydryl groups, decreased the particle size of the protein particles, and increased the specific surface area, which was beneficial to improve the functional properties of soy protein isolate. When the jet cavitation pressure was increased to 2.0MPa, the high pressure and extreme heat decreased the functional properties of soy protein isolate. At the same time, the functional properties of the extracted soy protein isolate and commercial soy protein isolate were compared, the results characterized the jet cavitation process in improving the utilization value of protein in high temperature soybean meal.