Abstract: A method for manufacturing trench MOSFET device with low gate charge includes the steps of providing a substrate of first conductivity type; forming an epitaxial layer of first conductivity type on the substrate; forming a body region of second conductivity type in the epitaxial layer, the body region extends downwards from the surface of the epitaxial layer; forming a plurality of trenches in the epitaxial layer, the body region having the trenches formed therethrough; forming a first insulating layer on the body region and on an inner surface of each trench; forming a ploy-silicon spacer on the first insulating layer on an inner side-wall of each trench; filling a dielectric structure in the lower portion of each trench; and filling a ploy-silicon structure on top of the dielectric structure in each trench. Through the trench MOSFET device, the gate capacitance and resistance thereof are reduced so the performance is increased.