Poly(epsilon-caprolactone) (PCL)/silicon-substituted carbonate apatite (Si-CO3Ap) composite derived from the interconnected porous Si-CO3Ap reinforced with molten PCL was prepared. PCL was used to improve the mechanical properties of a porous apatite by a simple polymer infiltration method, in which the molten PCL was deposited through the interconnected channel of porous Si-CO3Ap. The PCL covered and penetrated into the pores of the Si-CO3Ap to form an excellent physical interaction with Si-CO3Ap leading to a significant increase in diametral tensile strength from 0.23 MPa to a maximum of 2.04 MPa. The Si-CO3Ap/PCL composite has a porosity of about 50-60% and an interconnected porous structure, with pore sizes of 50-150 m which are necessary for bone tissue formation. These results could pave the way for producing a porous, structured biocomposite which could be used for bone replacement. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013