A novel porous composite scaffold of nano-HA/poly (lactic-co-glycolic) (PLGA) was fabricated by solvent casting/particulate leaching method. Chondrocytes were isolated from the knee articular joints of a rabbit, and then seeded in the scaffolds. The cell-loaded scaffolds were cultured in vitro for 5 days before implantation. Full-thickness articular cartilage defects were created in rabbits, and filled with and without the cell-loaded nano-HA/PLGA scaffolds. The implants were harvested after in vivo incubation of 2 and 5 weeks. Cartilaginous tissues were observed at defects repaired with the cell-loaded scaffolds, while only fibrous tissues were found for the control groups. The repaired tissues were evaluated histologically by hematoxylin and eosin staining. Results revealed that nano-HA/PLGA composite scaffolds facilitated adheration of cells in vitro, and the nano-HA particles could prevented the scaffolds from collapsing and promoted the formation of cartilaginous tissue in vivo.