Porous n-HA/PVA hydrogel composite was prepared through in-situ hydrothermal treatment under normal pressure and emulsion foam freeze-drying method, which was used to fabricate porous hydrogel. The pores exhibited interconnection-pore structure owing to the injection of air bubbles and the removal of emulsifier (OP). The porous hydrogels were investigated by using IR, XRD, TEM and SEM. The results indicated that n-HA in the composite could disperse uniformly, and there were chemical bonding with PVA. In addition, nano-hydroxyapatite existed in the composite in the shape of short-rod. The pores were interconnection with narrowly pore size and highly porosity. And the pore size and size distribution were influenced by the weight of OP. The emulsion foam freeze-drying method can be used to prepare porous hydrogel scaffold for tissue engineering, or to contain proteins scaffold, because of operating at a low temperature. The method displayed a vast potential of applied foreground.