Dyeing process using a natural dye on keratin fibres that have undergone permanent reshaping The present invention relates to a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, in which: a) an aqueous alkaline composition comprising one or more alkaline agents in an amount such that the pH of the composition is greater than at least 10 is applied to the said fibres, or a reducing composition comprising one or more reducing agents and then an oxidizing composition are applied to the said fibres, b) the said fibres are optionally rinsed, c) optionally, the treatment is neutralized, and the fibres are washed with shampoo and rinsed, d) optionally, the fibres are dried or left to dry, e) a dye composition comprising, in a cosmetically accept able medium, one or more natural dyes is applied to the said fibres, f) optionally, the fibres are washed and rinsed, g) the fibres are dried or left to dry.