Abstract: Functional properties of soy bean protein isolated(SPI) by high pressure homogenization(1~120 MPa),adding flaxseed gum(FG),konjac powder(KGM),carboxymethylcellulose sodium(CMC) were studied. The results showed that the addition of flaxseed gum made SPI solubility and emulsification increased significantly,reaching the maximum pressure of 120 MPa,but the emulsion stability with high pressure reduction. SPI-KGM system showed best foamability and foam stability at 30 MPa homogenization pressure.The water holding capacity decreased after homogenization,and adding polysaccharide did not improve the water holding capacity of SPI. The fatbinding capacity of SPI-FG reached the highest value at 90 MPa. The functional properties of SPI-CMC had been raised at high pressure homogenizati-on,but the effect was not very obvious.In summary,high pressure homogenization had different degrees of improvement for the functional properties of SPI and SPI-polysaccharide system.