The present invention concerns a cleaning-agent composition of which the surface comprises a powder which is hydrophobic, and more specifically, relates to a cleaning-agent composition in which the alkyl group of a surfactant attached to the surface is oriented towards an outermost shell, and of which the surface comprises a powder modified so as to be hydrophobic. When using the cleaning-agent composition of the present invention, of which the surface comprises a powder modified so as to be hydrophobic, it is possible to minimise the anionic surfactant content and to produce a cleaning agent having outstanding cleaning power and foaming power even while minimising irritation of the skin.