The present invention relates to a composition for washing keratinous substances, preferably keratinous fibers, comprising, in a cosmetically acceptable aqueous medium, at least one anionic or nonionic, amphiphilic linear block copolymer comprising at least one hydrophobic block and at least one hydrophilic block, with the exception of block copolymers of ethylene oxide and of propylene oxide, block copolymers comprising urethane units and block copolymers comprising siloxane units, at least one nonvolatile silicone, and at least one anionic surface-active agent in combination with at least one nonionic and/or amphoteric surface-active agent, and to the use of such a composition for washing keratinous substances.