The physiochemical properties of dried yam (Dioscorea batatas) by freeze dryer, cold-air dryer or hot-air dryer were examined for chromaticity, water absorption index (WAI), water soluble index (WSI), rehydration, viscosity properties and pasting properties. Freeze dried yam was maintained higher degree of lightness and higher WAI and WSI than those of cold-air or hot air dried one. In the case of rehydration, freeze dried yam was restored within one hour. The viscosity properties of freeze dried yam were the highest viscosity in all shear rates. Freeze dried yam was milled by roll mill (RM), pin mill (PM) or jet mill (JM) to evaluate for particle size, starch damage, pasting property and microstructure. Particle size was JM < PM < RM as 13.85~112.50 μm. In the result of starch damage, it was the highest value as 8.83 in JM, was the lowest value as 7.47 in RM. In pasting property, JM had relatively low viscosity at all shear rates. In the Microstructure by measuring scanning electron microscope, JM particle surfaces were rough with high starch damage, and particle size was confirmed fine particles in JM.