The invention relates to an improved planear insulated gate bipolar transistor, belonging to the technical field of a power semiconductor device. In the invention, a body electrode structure is introduced into the traditional planar non-penetrating type inulated gate bipolar transistor and is positioned in an N<-> drift area between two P-type base areas 5, is enclosed by a silicon dioxide oxidation layer of a body electrode and comprises recessed polycrystalline silicon body electrodes. By optimizing the voltage of the body electrode, the defect that the electric field of the traditional recessed gate type insulated gate bipolar transistor is concentrated under a recessed gate can be improved, the peak electric field at the bottom of the recessed gate is effectively reduced, and the puncture voltage of the device is improved; in addition, when the device is conducted forwards, the voltage of the body electrode can form a multicarrier accumulation layer at the outer side of the thick oxidation layer of the body electrode, thereby reducing the conduction resistance and further reducing the on-state loss in forward conduction.