Total dose irradiation and annealing effects of domestic partially-depleted SOI PMOSFET were studied. It is found that the back gate is more sensitive to total dose irradiation. It is the deep level interface traps that mainly decrease the saturated current. During annealing, it is the interface traps that determine the balance position of the top gate sub-threshold curve. While the tunneling and thermal emission electrons can only neutralize parts of the oxide traps in the buried oxide, making the back gate sub-threshold curve negatively away from the original one after a long time annealing.