Abstract: A method of fabricating a power metal oxide semiconductor field effect transistor (MOSFET) is provided, and the method includes forming a semiconductor layer on a substrate, forming at least one first trench in the semiconductor layer, forming a thermal oxide layer on a surface of the trench, forming a first gate in the first trench, forming a chemical vapor deposition (CVD) oxide layer on the first gate in the first trench, forming a mask layer on the CVD oxide layer in the first trench so as to form a second trench between the mask layer and the thermal oxide layer, and forming a second gate in the second trench.