Corn starch processing complex enzyme is a special enzyme product, mainly composed of cellulase and xylanase, for corn starch processing. In order to explore the technological effect of complex enzyme in the wet processing of corn starch, the application of complex enzyme in the washing process of corn fiber was studied in this paper. The changes of viscosity of corn starch slurry and the water absorption of fiber, yield of starch and protein, steam consumption and other parameters after enzyme reaction were investigated. The results show that the enzyme could decompose the endosperm starch cell wall and seed coat fiber of corn, wash the fiber smoothly, reduce the free starch content from 4.1% to 2.4%, increase the starch yield by 0.07%, reduce the fiber moisture by 3.7% after dehydration, and save steam consumption effectively in the fiber drying process. The results of research on application test are as follow: the use of composite enzyme preparation can quickly and effectively degrade the viscosity of corn starch slurry and the water absorption of fiber, effectively separate starch and protein, improve the washing effect of fiber, increase the yield of starch and protein, reduce the consumption of steam and electricity, and improve the utilization rate of equipment.