Star-shaped hydroxy-terminated poly(D,L-lactide) (s-PDLLA), with arms of different lengths, were obtained by ring-opening polymerization (ROP) of D,L-lactide (LA) initiated by varied contents of pentaerythritol (PETH) in the presence of stannous octoate (Sn(Oct)(2)), and were condensed with carboxyl-terminated poly(ethylene glycol) methyl ether (CT-mPEG, M-n = 850 and 2,000) to afford four-arm star-shaped poly(D,L-lactide)-block-poly(ethylene glycol) copolymer (s-PDLLA-b-PEG). The polymers, including s-PDLLA, CT-mPEG, and s-PDLLA-b-PEG, were characterized and confirmed by H-1-NMR and C-13-NMR spectroscopy, fourier transform infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC).