Abstract: A method for calculating 3 D discharge flow in a centrifugal impeller is developed by means of solving the incompressible steady time averaged N S equations,the continuity equation and the k ε turbulence model equation.This method is accomplished with calculation grids generated by an algebraic transformation,and thus it can be easily applied to the design analysis of centrifugal impellers.The discharge flow of a three dimensional shrouded centrifugal compressor impeller was measured for assessing the validity of the present calculation procedure.The comparison between the experimental data and the calculation results shows that the present method can predict the mean velocities.