As surfactant is the major component in detergent formulations, many studies have been performed to develop surfactants with improved biodegradability and mildness in the fields of all household products. The newly systhesized surfactants during this study are the multi-functional surfactants having dual function of cleaning and skin care / fabric care effects. Since these amine oxide type amphoteric surfactants have the bulky dialkyl amido chain structure, they show characteristics of nonionic surfactants in an alkaline condition, while showing characteristics of cationic surfactants in a neutral condition. Therefore, they can serve as dual function surfactants by a single molecule through the interconversion of cleaning and softening effects depending on pH variations of the aqueous solution. As the common used surfactants have molecular weights from 400 to 600, they can penetrate to the human skin easily. But, these newly synthesized surfactants have molecular weights from 800 to 1600, therefore we expect that they cannot penetrate to the human skin easily. In this study, new amphoteric surfactants have been synthesized and their physical properties such as surface tension, critical micelle concentration (CMC) and contact angle were measured. Also their cleaning/softening effects with pH were discussed.