A depletion mode 4H-SiC MOSFET for RT applications is studied using drift-diffusion physical device simulations. The structure is basically the same as for a MESFET. A MOS gate with a 30 nm thick SiO2 layer replaces the Schottky gate. A 40% increase in the drain current was observed for a positive gate bias of 7 V compared to 0 V. The small signal AC analysis showed f(T) and f(max) to be 15.7 and 52.9 GHz respectively.