In order to examine mono-component soiled cloths for theoretical detergency studies we studied the preparation process and whether detergency can be calculated by reflectance. We used carbon black soiled cloth (a hydrophobic particulate soil), iron oxide ( Ⅲ ) soiled cloth (a hydrophilic particulate soil), and hemoglobin soiled cloth (a slightly water soluble soil). We found that various methods for removing the stains from the soiled cloths may be used to obtain moderate soil removal efficiencies. Carbon black soiled cloth can be prepared by using 2-propanol as a dispersion solvent and then soiling it with an automatic universal shaker. Iron oxide ( Ⅲ ) soiled cloth can be prepared by soiling it with Terg-O-Tometer after an ultrasonic dispersion process. Hemoglobin soiled cloth can be prepared using a steam heating process after soaking it with a fixed volume of hemoglobin solution. It was confirmed that the removal ratio of each of the three kinds of soiled cloths calculated using the K/S value of surface reflectance can be converted into a quantitative soil removal ratio.