A honeycomb laminate was formed with ceramic fiber paper and was then heat-treated. It was impregnated with a dispersion of high silica zeolite, inorganic binder and silica sol, and was dried to get a honeycomb rotor of adsorbent for the VOC concentrating rotor.The removal efficiency of the rotors, which were installed in a testing unit and user＇s actual units, was examined for several variables, such as the rotation speed, the face velocity of desorption air, the effect of VOC concentration ratio, f, on the fractional removal of the rotors etc. The result showed that the optimal rotation speed of the VOC concentrating rotor was expressed by a nondimensional number, U-R/(f.n(opt)L) = 450, and that the rotor removed more than 90% of the VOCs laden in the process gas stream with its concentration ratio of 10 times in the desorption gas stream with the suitable combinations of the variables mentioned above.