The invention discloses an enhanced Ga2O3 metal oxide semiconductor field effect transistor and a manufacturing method thereof, which mainly solve the problem of complex manufacturing of similar devices in the prior art. The enhanced Ga2O3 metal oxide semiconductor field effect transistor comprises a substrate, an epitaxial layer and an insulated gate dielectric layer from bottom to top; a sourceelectrode and a drain electrode are arranged on the epitaxial layer, and a gate electrode is arranged on the insulated gate dielectric layer. The thickness of the insulated gate dielectric layer is 10-30 nm; the epitaxial layer is an n-type Ga2O3 epitaxial layer, the thickness being 150-300 nm, and the electron concentration being 2.0 * 10 < 16 >-1.0 * 10 < 18 > cm <-3 >. The manufacturing key ofthe device is that before an insulated gate dielectric layer is deposited, the temperature of a cavity is set to be 200-500 DEG C, and O3 is introduced into an ALD reaction cavity to treat the surfaceof an n-type Ga2O3 channel layer for 5-15 min. The interface state density and static power consumption of the device are reduced, the threshold voltage is increased, the manufacturing cost and difficulty are reduced, and the method can be used for power devices and high-voltage switching devices.