We investigated power requirements and pressure drop in the gas-solid stirred fluidized bed with vertical blades when increased rotational speed up to 6s-1 At high rotational speed the minimum torque for stirring was greater than predicted by the approximate equation at low rotational speed, because of the centrifugal force acting on the particles. Then we corrected the approximate equation of minimum torque for stirring by considering centrifugal force. This corrected equation correlated well with experimental values. The pressure drop at high rotational speed behaved the same as in a spouted bed. © 1988, The Society of Chemical Engineers, Japan. All rights reserved.