The corosion resistance of electrophoretic gradient film thickness samples and finish samples prepared by dfferent processes were investigated by using the enhanced corrosion test method of automobile.During the preparation of the lest panel,a variety of body outer panel materials and pretreatment processes were selected for combined verification.The prepared electrophoretic test panel and finish test panel were subjected to the vehicle enhanced corrosion test,and the test verification results were analyzed and discussed,so as to provide reference for understanding the corosion resistance of coating films of diferent body materials.