The aim of the current study is to design amphiphilic poly É›-caprolactone/polyethylene glycol nanoparticles (PCL/PEG) having better physicochemical properties than the PCL nanoparticles for protein delivery. Bovine serum albumin poly É›-caprolactone and polyÉ›-caprolactone/polyethylene glycol nanoparticles were designed by the double emulsion/solvent evaporation method. Size was checked by photon correlation spectroscopy technique using Malvern zetasizer. Zeta potential wasmeasured by laser anemomerty technique using Malvern zetasizer. Protein loading efficiency and release rate were analysed by bicinchoninic acid assay using plate reader spectrophotometer. Morphology and size of the particles were displayed by scanning electron microscopy. All the (PCL/PEG) blends produce nanoparticles with smaller sizes, narrower PDI(s), and higher protein release rates than the BSA loaded LPCL nanoparticles. The low molecular weight polyethylene glycol (SPEG) blended (LPCL/SPEG2.5% and LPCL/SPEG5%) nanoparticles have higher protein loading efficiencies, smaller sizes, narrower PDI(s), and higher protein release rates than the BSA loaded LPCL nanoparticles.