A series of amphiphilic hyperbranched poly (amine-ester)-poly (lactide-co-glycolide) (HPAE-co-PLGA) copolymers were synthesized by ring-opening polymerization of dl-lactide, glycolide and a fourth generation hyperbranched poly (amine-ester) (HPAE-OHs4) with Sn(Oct)(2) as catalyst. The chemical structure of copolymers was characterized by Fourier transform infrared (FT-IR), nuclear magnetic resonance (H-1-NMR, C-13-NMR), thermo gravimetric analysis apparatus (TGA), and different scanning calorimetry (DSC). Formation and characteristics of polymeric micelles of the amphiphilic copolymer were studied by environmental scanning electron microscopy (ESEM), fluorescence spectroscopy, and dynamic light scattering (DLS). In order to estimate the feasibility as novel drug carriers, a lipophilic model drug amphotericin B was incorporated into polymeric micelles and the drug release behavior was investigated. The micelle size and drug-loading content were found increased, and the drug-release rate decreased with the increase of molar ratio of dl-lactide/glycolide to HPAE.