The catalytic performance of zeolite β in the liquid phase alkylation of benzene with propylene is compared with that of other zeolites: MOR, ERB-1, USY, MTW. The comparison is carried out both by catalytic tests and by computational evaluation of the energy barriers for diffusion of the product molecules and of the binding energies (BE's) of the same molecules, inside the zeolite pores. Among the zeolites studied, zeolite β appears to be one of the most efficient catalysts, producing the smallest amount of propylene oligomers and of n-propylbenzene. The energy diffusion barriers and the BE's, both calculated for cumene and DIPB isomers account for the outstanding performance of zeolite β.