The problems such as difficult cold start,parts abnormal abrasion,rubber parts swelling,oil emulsification,oil coking,oil sludge often occur in a methanol engine during bench test.Based on the characteristics of methanol fuel and its effect on engine oil,the change in abrasion of methanol engine and lube oil physicochemical properties was investigated using different types of lube oils in bench test.The results indicate that the abrasion of methanol engine and the oil coking can be significantly reduced by adjusting oil additive and viscosity level.