The present invention relates to a process for dyeing keratin fibers, in particular human keratin fibers such as the hair, using a) one or more blue, violet or green dyes and b) one or more disulfide, thiol or protected-thiol fluorescent dyes.The present invention also relates to a cosmetic composition comprising the dyes defined above, and also to a multi-compartment device containing said dyes.The present invention also relates to the use of said dyes for dyeing light keratin fibers, notably human keratin fibers such as the hair, in chestnut-brown, dark chestnut-brown, brown, brown with a tint, or even black, without using an additional dye other than those defined above.
