The invention discloses a compound enzymatic hydrolysis method for straw raw materials, which comprises: hydrolyzing the straw raw materials by diluted acid to decompose lignin; adding xylanase, cellulose, amylase, pectinase and beta-glucanase, and adjusting the pH value of the mixture to 4.3 to 5.5 by using an acidic matter or alkaline matter; and performing enzymatic hydrolysis at 40 to 55 DEG C for 24 to 72 hours. In the invention, a compound enzyme method is used to perform enzymatic hydrolysis on straw to convert the straw into reducing sugar, a proper mixing ratio of compound enzymes isselected to allow enzymes to interact to maximize the hydrolysis, the concentration of the reducing sugar generated by the enzymatic hydrolysis is high, the yield of sugar is high, the enzymatic hydrolysis conditions are mild, adverse influences on fermentation in a later period are avoided, the growth of a strain for fermentation in the later period is not inhibited, the ethanol yield during fermentation is high, the investment and cost are small, and thus, the method is suitable for large-scale use in industry.