Porous hydroxyapatite (HAp) scaffolds were successfully prepared by using the HAp slurry based on the replication of polymer sponge substrate. The effect of HAp content in slurry on the pore morphology and size, and density, porosity, and mechanical strength of porous scaffolds was investigated. The scaffolds with average pore sizes ranging from 200 to 400 µm had an open, relatively uniform, and interconnected porous structure. As the HAp content increased, the porosity of scaffold decreased while the density increased. These phenomena were attributed to the fact that the pores became interconnected with more dense and thicker pore walls with increasing HAp content in slurry. The results suggest that the density, porosity, and compressive strength of the porous HAp scaffold were significantly affected by the content of the HAp powder in the slurry.