Submicron hydroxyapatite powder with particle size in the range of 80-250 nm was fabricated by sol-gel process in our laboratory. To make ceramic slurry with good flowability, the powder was mixed with binder and distilled water. The binder was consisted of acid magnesium and aluminum phosphates. The polyurethane foam was impregnated in the slurry, squeezed out the excess slurry and the composite porous body gained. Green body was dried in room temperature naturally and then moved to electric furnace and sintered at high temperature. The sintered scaffolds possess interconnected open pore structure and with a porosity of 70-85% and compressive strength 10-20 MPa, and was consisted of doped HA and other phosphates. The scaffolds were co-cultured with osteoblasts in vitro. SEM analyses revealed that the cells adhere to the ceramic surface, proliferate and growth properly. Experimental results showed that the scaffold possesses good biocompatibility and could be used in bone tissue engineering.