An experimental study was conducted on a drug delivery system (DDS), using porous apatite ceramics (PAC): hydroxyapatite block (HAb) [Ca10(PO4)6(OH)2] having a porosity of 35–48% and pore size range of 50–300 μm, and β-tricalcium phosphate block (TCP) [Ca3(PO4)2] having a porosity of 75–80% and pore size range of 100–400 μm, for sustained release of a chemotherapeutic agent. Methotrexate (MTX) was loaded in the pores of PAC blocks by centrifuging the blocks in MTX solution. Impregnation of MTX in PAC blocks (1 cm3) was confirmed by a magnetic resonance imaging (MRI) study using Gadolinium-DTPA enhancement. The MRI showed high signal intensity in the PAC, which was confirmed by dye loading into the pores. To estimate the MTX-releasing capability of the PAC, the blocks were stored in 3 mL of phosphate-buffered saline (PBS) at 37°C and the PBS was replaced every 48 h. The amount of MTX released was assayed by high-performance liquid chromatography. This study showed that MTX-impregnated PAC (0.63–2.25 mg/block) released the drug in a steady manner and maintained its concentration (0.1–1.0 μg/mL) up to 12 days. This concentration is high enough to be effective against tumor cells. Chemotherapeutic agent–impregnated PAC, prepared by simple centrifugation, could be a valuable form of local chemotherapy when used as a strut graft to repair bone defects. This new DDS material could also be used as an adjuvant to extended curettage and provide a means to reduce the recurrence of tumors without risk of systemic toxicity. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 39, 536–538, 1998.