In this work, novel antibacterial composites were prepared by using poly(epsilon-caprolactone) (PCL) as the main matrix material, and gentamicin-loaded microspheres composed of beta-tricalcium phosphate (beta-TCP) and gelatin. The purpose is to use this biodegradable material as a support for bone tissue. This composite system is expected to enhance bone regeneration by the presence of beta-TCP and prevent a possible infection that might occur around the defected bone region by the release of gentamicin. The effects of the ratio of the beta-TCP/gelatin microspheres on the morphological, mechanical, and degradation properties of composite films as well as in vitro antibiotic release and antibacterial activities against Escherichia coli and Staphylococcus aureus were investigated. The results showed that the composites of PCL and beta-TCP/gelatin microspheres had antibacterial activities for both bacteria. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013