The reaction of 1-butene and isobutene with ammonia has been investigated, far from thermodynamic equilibrium, in the pressure range 1-6 MPa over a series of acidic zeolites. The kinetics are compatible with a Langmuir-Hinshelwood mechanism involving adsorbed species. The rates of amination increase with the Si/Al ratio of the solid. A small influence of the zeolite structure is noticed on the relative adsorption coefficients in the case of 1-butene but not in that of isobutene. The catalytic activity calculated per proton is higher on MFI than on BEA or HY zeolites, but this effect of the structure is less than an order of magnitude. Under the conditions of reaction used in this work large pore zeolites show a good resistance to deactivation. It is proposed that deactivation is mainly due to the formation of strongly basic polyalkylamines and not to coke.