An anomalous total dose effect that the wider channel device is more susceptible to total ionizing dose than the narrow one is observed with the 0.13 mu m H-gate partially depleted silicon-on-insulator technology. The measured results and 3D technology computer aided design simulations demonstrate that the devices with different channel widths may exhibit an enhanced reverse narrow channel effect after radiation. This is because in the case of bias of TG irradiation, there will be an electric field from source to drain to the body area, which will affect the electric field linear density of the source and drain to the buried oxygen layer area. Compared with narrow-channel devices, the electric field from drain/source to body region via box region of wide-channel devices accounts for a larger proportion, and the more oxide trap charges will be generated, which will cause greater damage.