Propylene transformations in the presence of high-silica zeolites and galloaluminosilicates at temperatures of 150-600degreesC and volume rates of 300-900 h(-1) were studied. It was found that the main transformation products are mixtures of aliphatic and aromatic hydrocarbons, whose ratio is varied depending on the process conditions. The obtained results were compared with known data concerning propylene transformations on faujasites.