Detergency effect was analyzed in terms of interfacial-chemistry parameters of rolling-up effect. Polyester film was used for substrate, the mixture of liquid paraffin containing 5% oleic acid was used for oily soil and LAS alone and the mixed of LAS and nonylphenol polyoxyethylene ether having various mole numbers of ethyleneoxide adducts were used for surfactants. The removal process in a form of droplet was analyzed by measuring interfacial tension at oily soil and surfactant solution, contact angle between substrate and oily soil. Interrelationship between the detergency and the rolling-up was also examined by washing artificially-soiled fabric in those surfactant solution. The results showed that the oily soil was more easily removed with lower interfacial tension at oily soil and surfactant solution and with larger maximum contact angle at equilibrium state. In comparison LAS with mixture of surfactant solutions, performance of the mixed solution was better than of LAS alone. In case of mixed solution, the solution with the higher content of nonylphenol polyoxyethylene ether, the lower interfacial tension and the higher maximum contact angle were observed.