The invention concerns a composition comprising, in a physiologically acceptable medium, at least a liquid fatty phase comprising at least a volatile organic solvent and at least an aqueous phase. The invention is characterised in that the aqueous phase contains a micro-dispersion of wax particles. The composition results, after being applied on keratinous fibres, in a water-resistant film and provides good curved shape to the keratinous fibres. The invention is applicable to mascara.