The present invention relates to a cosmetic composition comprising:a) a supramolecular oil (compound A) which can be obtained by reaction between an oil bearing at least one nucleophilic reactive function and a joining group capable of establishing hydrogen bonds, said joining group bearing a reactive function capable of reacting with the reactive function borne by the oil, and said joining group also comprising at least one unit of formula (Ia) or (Ib):b) a polyalkene-based supramolecular polymer (compound B) which can be obtained by reaction of a functionalized polyalkene polymer with a functionalized joining group, said joining group being capable of forming at least three H (hydrogen) bonds.The invention also relates to a cosmetic treatment process using said composition.