The present invention relates to a dye composition comprising at least one oxidation dye precursor, at least one polycondensate of ethylene oxide and propylene oxide having the following structure: H—(O—CH2—CH2)a—(O—CH(CH3)—CH2)b—(O—CH2—CH2)a—OH, in which a and a′ range from 2 to 150 and b ranges from 1 to 100 and at least one anionic surfactant of polyoxyalkylenated fatty acid type, the weight ratio between the polycondensate(s)/the polyoxyalkylenated fatty acid(s) ranging from 0.05 to 1. The invention also relates to a dyeing process using this composition after mixing with a composition comprising an oxidizing agent. Another subject of the invention is devices comprising at least two compartments, the first compartment comprising the above composition and the second compartment comprising a composition comprising at least one oxidizing agent.
