A method for fabricating a super-junction semiconductor power device with reduced Miller capacitance includes the following steps. An N-type substrate is provided and a P-type epitaxial layer is formed on the N-type substrate. At least a trench is formed in the P-type epitaxial layer followed by forming a buffer layer on interior surface in the trench. An N-type dopant layer is filled into the trench and then the N-type dopant layer is etched to form a recessed structure at an upper portion of the trench. A gate oxide layer is formed, and simultaneously, dopants in the N-type dopant layer diffuse into the P-type epitaxial layer, forming an N-type diffusion layer. Finally, a gate conductor is filled into the recessed structure and an N-type source doped region is formed around the gate conductor in the P-type epitaxial layer.