Sodium niobate (NaNbO3) particles with plate-like morphology and hexagonal unit cells were prepared by the hydrothermal method. The result of SEM showed that the hexagonal NaNbO3 were characterized by plate-like morphology with a diameter of 5-15 mu m and a thickness of 1-2 mu m. The crucial influences on the morphology and crystal phase of the NaNbO3, such as concentration of [OH-], surfactant, and K+:Na+ ratio, were established. By further calcination treatment, the plate-like hexagonal NaNbO3 particles could be completely transformed into perovskite structure without morphology change. The XRD and EBSD results indicate that the major face of the calcined particles is parallel to the crystallographic (001)(pc) (pseudo cubic index) plane. Compared with the traditional high-temperature molten salt method, this work provides a simpler way to prepare the template for fabricating textured ceramics.