The present invention concerns a novel, sterile and injectable aqueous composition, that is heat-sterilised, comprising at least crosslinked hyaluronic acid, or one of the salts of same, and one or more fatty acids, characterised in that the mass proportion of water is greater than 51% of the total mass, the mass proportion of fatty acid is less than 45% of the total mass, the viscoelasticity properties are such that the ratio G″/G′ at 0.7 Hz is less than 0.70; a method for preparing said composition; and the use of said composition for aesthetic and therapeutic applications.