Extraction methods of hwangto, that is, elutriation(by water) and ball-milling, were investigated by particle distribution analysis, X-ray diffraction and UV-Vis spectrometry. Particle size and shape of hwangto influenced the surface reflectance and the color of cotton fabric. Cotton fabric dyed with ball-milled hwangto showed reddish yellow color compared with that of elutriated one. With increase in ball mill time, particle size of hwangto decreased but the K/S value obtained at λ$_{max}$ of 440 nm increased. Higher K/S value was obtained with narrower particle size distribution.n.