The wear rate of high C-Cr steel (AISI 52100) has been measured when lubricated with gasoline, ethanol, and water. The wear experiments were performed in air and argon in order to study the relationship between the wear and load, the water-ethanol content in gasohol, and the atmosphere. A larger wear rate was found in gasohol, having a constant ethanol content which was completely dissolved. Among gasohols of different ethanol content and involving hygroscopic water, the highest wear rate of steel was found to be in gasohol with about 20 percent ethanol content. It is concluded that the wear of steel in gasohol is caused by corrosive wear, which is jointly affected by oxygen and water.