Through the surface response method, based on the Box-Behnken test principle, a three-factor test was carried out on non-catalytic pyrolysis of biomass (corn straw), which the bio-oil yield is the response value, and the temperature, heating rate and nitrogen flow rate are independent variables. Process parameters to determine the maximum bio-oil yield for catalytic pyrolysis. Using tetraethyl silicate as the silicon source, a composite catalyst ZSM-5/SBA-15 was synthesized by post-synthesis method, and the microwave catalytic pyrolysis product analysis of corn straw was carried out. The catalysts were characterized by XRD, SEM, TEM, NH3-TPD, and draw conclusions the composite catalyst not only had the properties of mesoporous catalyst SBA-15, but also had the properties of microporous catalyst ZSM-5. Through GC-MS analysis, the addition of the composite catalyst ZSM-5/SBA-15 increased the content of hydrocarbon (6.42%) and phenol (39.65%) compared with that of non-catalytic pyrolysis.