Abstract: A continuous mixed flow reactor, in which the supported heteropolyacid catalyst HRP-12 was suspended, was adopted in the experiment. Experimental data were used in parameters estimation for kinetics equation of benzene alkylation with linear olefin. Parameters, including reaction rate constant, activation energy and reaction order in olefin molar concentration, were determined as 13 530 s－1, 48743Jmol－1 and 1 respectively. The kinetic equation for benzene alkylation with linear olefin was thus established. Statistics test and model prediction have shown that the kinetics equation is highly credible under the condition α=0.05 and well corresponds with reaction principle.