The present invention relates especially to a composition for dyeing keratin fibers, in particular human keratin fibers such as the hair, comprising: (i) one or more fatty substances in a content ranging from 40% to 85% by weight relative to the total weight of the dye composition, (ii) one or more oxyethylenated fatty alcohols with an oxyethylene number of less than or equal to 10, and (iii) one or more nonionic surfactants of alkylpolyglucoside type, (iv) optionally one or more alkaline agents, (v) one or more direct dyes which are preferably cationic, anionic or neutral. The present invention also relates to a process for dyeing keratin fibers, comprising the application to the said fibers of an above mentioned composition, optionally in the presence of a composition comprising one or more chemical oxidizing agents; the dye composition possibly resulting from the mixing of several compositions. Finally, the invention relates to devices that are suitable for performing this process.