The invention provides an energy-saving power generation device, which comprises a transmission shaft, a generator set, a magnetic suspension module, a magnetic radial balance module and a magnetic axial balance module, wherein the above parts are arranged in a base; the magnetic suspension module is used for connecting the permanent magnet ring of the transmission shaft with the magnetic force effect matched with the magnetic force ring group in the conical ring groove of the fixing plate; the transmission shaft can vertically rotate at a high speed in a suspension manner; the magnetic radialbalance module is matched with the annular magnetic group for connecting the magnetic ring of the transmission shaft and the positioning plate to generate radial magnetic repulsion; the magnetic axial balance module is matched with a second magnet piece connected with the transmission shaft and a first magnet piece in the seat plate to generate axial magnetic repulsion; radial and axial shaking and swinging of the transmission shaft during high-speed rotation are reduced; by means of the structure that the permanent magnet ring of the magnetic suspension module is matched with the magnetic ring set in the conical ring groove, the magnetic ring of the magnetic radial balance module is matched with the annular magnetic set in the ring groove and the like, the technical means of expanding the magnetic force action range in the radial direction is adopted, and the energy-saving power generation device can reduce the overall height and be flattened.