Abstract: The organopolysiloxane composition of the invention is a highly viscous liquid or paste suitable as a base of pasty cosmetic and medicinal preparations such as creams, hair-dressings, ointments and the like. The composition comprises an oligomeric cyclic organopolysiloxane compound, an oleaginous material and a cellulose ether esterified with long-chain alkanoyl groups as the thickening agent. The cosmetic and medicinal preparations prepared from the inventive composition as the base have good spreadability on the human skin and are capable of giving very refreshing feeling to the user or patient without lasting stickiness.