Power Metal Oxide Semiconductor Field Effect Transistor(MOSFET) is widely used in power Integrated Circuit(IC). Radiation in space may cause the leakage current at the edge of the channel in power MOSFET, which will lead to the degeneration of power IC. This paper presents a new waffle layout for power MOSFET in 0.35 μm Bipolar CMOS DMOS(BCD) process. Packaged power MOSFETs with finger and waffle layout are tested after Co-60 based irradiation experiment. The Total Ionizing Dose(TID) radiation induces the leakage current only in N-channel power MOSFET with finger layout. The presented waffle layout with its edgeless structure is proved to be effective to control the leakage current, which enhances the TID-tolerance of power MOSFET a lot.