Abstract <p>New amphiphilic betulin- and oligo(ethylene glycol)-containing polymethacrylate molecular brushes are synthesized by the radical homopolymerization of the first synthesized macromonomers, oligo(ethylene glycol)betulin methacrylates, as well as by the copolymerization of betulin methacrylate with oligo(ethylene glycol) methacrylates (in the second case, the reactivity ratios of the comonomers are determined). It is shown that differences in the architecture of homopolymer and copolymer molecular brushes (different arrangement of oligo(ethylene glycol) fragments in side chains) affect the behavior of the polymers in aqueous solutions.</p>