Abstract: Experimental study on the influence of impinging distances , the volume and the form of the impinging chamber and different particulate materials on the process of impinging stream drying (ISD) was performed on an experimental coaxial impinging stream dryer, and a number of important conclusions were drawn. The test results showed that the longer the impinging distance is, the better the effect of drying is; and the larger the volume of the impinging chamber is, the better the effect of drying is. The effect of drying of the rectangular chamber was better than that of the cylindrical one. The experimental results also indicated that the impinging stream drying was more suitable to the powdered materials of high moisture content.