Composites of poly(3-hydroxybutyrate)-co-poly(3-hydroxyvalerate) (PHBHV) with 6% of 3-hydroxyvalerate (HV) and natural rubber (NR) were prepared by a solvent-casting method. Different approaches were tested for the composite preparation. Both PHBHV and NR were dissolved in chloroform, followed by its evaporation, giving various layers. The mechanical properties and morphology of the obtained composites were evaluated by tensile tests and scanning electron microscopy (SEM), respectively. The obtained results demonstrated that the final composite has excellent mechanical properties when compared with PHBHV. SEM analysis unequivocally showed the excellent adhesion between the two polymeric layers. This new material was also tested as a drug delivering system using flurbiprofen as a model drug, and then the diffusion coefficients were determined. This article describes an easy method to produce a desirable composite from PHBHV and NR. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 116: 718-726, 2010