Abstract: Fluid circulation,mixing and oxygen transfer processes were studied in a newkind of cell culture bioreactor with a novel centrifugal impeller.The advantages of the cell-lift impeller are incorporated,and the fluid circulation efficiency is enhanced sufficiently.Theoxygen transfer rate increases with aeration rate and rotating speed,with the former parame-ter being the most significantly.The volumetric oxygen transfer coefficients and the fluid cir-culation rates in the draft tube are correlated based on the experimental data.