Abstract: A continuous mixed flow reactor, in which the supported heteropolyacid catalyst HPR-12 were suspended, was used in the experiment. Experimental data were adopted in parameters estimation for model of deactivation kinetics of benzene alkylation. Parameters, including deactivation rate constant, deactivation activation energy, exponent of retaining activity coefficient and reaction order in olefin molar concentration, were determined. They are 12.057 2 m3/(mol·s), 70552J/mol, 1 and 2 respectively. The deactivation kinetics model for benzene alkylation with linear olefine was thus established. Statistics test has shown that the deactivation kinetics equations are highly credible under the condition α=0.005 and well correspond with principle of benzene alkylation.