The presence of allergenic proteins in cow milk limits its use as infant formula to a certain extent. Skimmed milk was used as raw material， the degree of hydrolysis， the IgG inhibition rate of skimmed milk and IgE inhibition rate of patients were used as indicators and the effects of alcalase and protamex compound treatment on its sensitization were investigated. The results showed that the most suitable conditions for the enzymatic hydrolysis were the substrate ratio (E/S) of alcalase and protamex was 6 000 U/g， the composite ratio for alcalase and protamex was 3∶1， and the hydrolysis time was 60 min， and the inhibition rate of the compound enzyme on skimmed milk IgG and IgE antibodies were significantly higher than that effect of the single protease treatment (P<0.05)， which were 86.94% and 43.46%， respectively， indicating that the compound enzyme is an effective method to reduce the allergenicity of skimmed milk.