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A method for assessing the corrosion properties of automotive gasolines containing oxygenates and the effectiveness of corrosion inhibitors for these fuels similar to the method in ASTM D 665 is examined. Data on its use are reported.One of the basic performance properties of automotive gasoline is corrosiveness, i.e., the ability to corrode metals in contact with it. This property of gasolines and the products of their combustion is a function of the presence of sulfur compounds, primarily mercaptans, water-soluble acids and bases, dissolved water, and acidity [1].Corrosive processes are especially intensive on the gasoline phase boundary -so called "tank-bottom water," i.e., water separated from gasoline during settling when the weather conditions change. European standard EN-228-2000 ( §5.6.1) requires adding anticorrosion additives to gasoline if there is the danger of separation of water. In view of the variety of climatic conditions in Russia, it is almost impossible to avoid separation of water during storage of gasolines.Due to the wide use of oxygen-containing compounds as antiknocks in automotive gasolines, so-called oxygenates (low-molecular-weight alcohols, C 5 and higher esters, etc.), the problem of their corrosiveness has become especially pressing. This is indicated by the many publications on the increase in the corrosiveness of gasolines containing methyl tert-butyl ether (MTBE), the most widely used antiknock additive. Oxygen-containing compounds in gasolines tend not only toward relatively rapid oxidation with formation of aggressive low-molecular-weight acids (formic, acetic, etc.), but also toward initiation of oxidation of the unstable hydrocarbons contained in the gasoline. This increases the acidity of the gasoline and consequently increases its corrosiveness. As a result, gas holes can appear in tanks and toxic products, MTBE in particular, can enter ground waters which are a source of drinking water.According to data in the foreign press, MTBE causes approximately 20 different disorders in the human body. On this basis, the question of prohibiting its use in automotive gasolines has been raised in the USA.