A kind of quick drying waterborne epoxy primer for construction machinery was developed.The coating surface dries quickly,the salt spray performance is good,the thick coating has no flow hanging and other coating defects.Waterborne epoxy primer was prepared by using different epoxy emulsions and waterborne amine hardener as base materials,adding pigments,anti-rust fillers,various additives,cosolvent.The influence of different epoxy emulsions and epoxy curing agents and their dosage,different facial base ratios,types and ratios of different thickening agents on the performance of coating and construction were mainly investigated.The waterborne epoxy primer for construction machinery with excellent comprehensive performance was finally developed through experiments.