The present invention relates to a cosmetic composition comprising, in a cosmetically acceptable medium, at least one non-nitrogenous zinc salt and at least one starch, in a weight ratio of the amount of starch to the amount of zinc element ranging from 0.01 to 20. Another subject of the invention relates to a process for treating keratin fibres, using such a composition, and to the use of such a composition, preferably in the form of a leave-on care product, for conditioning keratin fibres and for protecting their artificial colour from fading.
