The liquid - phase alkylation of benzene with 1-dodecene has been investigated in the presence ion- exchanged bentonite. The comparison of the activities of Fe3+, Al3+, and Zr 4+ exchange bentonite indicate that the best results were obtained with Fe3+ exchange bentonite. The influence of various reaction parameters such as reaction temperature, reactant feed ratio and catalyst amount affecting the activity and selectivity of Fe3+exchanged bentonite have been studied. The reactions were found to proceed under relatively mild conditions with excellent conversions, and a simple product isolation procedure was achieved. Fe3+ exchange could also be recycled and reused effectively for several times, thus rendering green characteristic to this reaction.