The main purpose of our study is to delineate the effect of Coal Water Mixture (CWM) properties on spray characteristics and to obtain the necessary data required for optimum burner design. Several experiments on the atomization of CWM will be carried out with twin fluid atomizers. The effect of CWM properties and atomizer type and conditions on the mean sizes and the size distribution of CWM sprays are investigated in detail. It is found that spray droplets become more ununiform in size as the concentration of CWM increases, and that minute droplets are more deformed and big ones are spherical. It is also found that for the Newtonian or pseudo plastic CWM the mean droplet size of CWM spray is almost the same as that of water with an Internal Mixing Atomizer, but is a little larger with a Half Mixing Atomizer.