A cosmetic composition comprising at least one silicone/acrylate copolymer and at least one non-cellulose thickening agent, wherein the at least one silicone/acrylate copolymer is obtained by radical-mediated polymerization of at least one ethylenically unsaturated monomer (a) in the presence of at least one silicone derivative (b) comprising at least one oxyalkylene group. A cosmetic process, in particular a process for fixing and/or holding the hairstyle by using said composition, as well as to the use of this composition for the manufacture of a cosmetic formulation intended in particular for holding and/or shaping the hairstyle.