Oligomerization reaction of light olefins serves as a useful tool to convert light olefins to products with higher boiling point range that can be used as gasoline, jet fuel or diesel components after hydrogenation. In the past few years, supported ionic liquids have emerged as useful catalysts in many organic reactions. In the present study, the application of a silica-supported Brønsted acidic ionic liquid in the oligomerization of 1-butene and 1-pentene is investigated. The possibility of the conversion of a low boiling point range fraction of polypropylene cracking product to jet fuel or diesel components is also taken into account.