Abstract: The test of discontinuous feeding process on the experimental table of conical paddy rice separator was done.The test data was treated and analyzed by Rose mixing rate equation, the mixing and separating rate constants were found.The relationships between separation of paddy rice and the rotating speed of conical vessel,the filling rate,the rotating period,the inclined angle of the shaft, the vessel inner surface condition were discussed. Through the test of continuous feeding process,the effect of rotating sepeed, feeding rate and the diameter of unloading on the paddy-rice separation and the optimum operating condition were found out.