The invention provides a reverse conducting insulated gate bipolar transistor. The reverse conducting insulated gate bipolar transistor comprises an N type substrate, a front-surface structure formed at the front surface of the N type substrate and a back-surface structure formed at the back surface of the N type substrate; the back-surface structure comprises grooves formed at the back surface of the N type substrate, back-surface P+ regions formed between the grooves, polysilicon arranged in the grooves and a back-surface metal layer which is formed on the back-surface P+ regions and the polysilicon. According to the reverse conducting insulated gate bipolar transistor, the polysilicon is adopted to fill the grooves at the back surface of the reverse conducting insulated gate bipolar transistor. When the reverse conducting insulated gate bipolar transistor is manufactured, it only needs to precisely control the doping concentration of the polysilicon so that the parameters of a reverse conducting diode at the back surface of the reverse conducting insulated gate bipolar transistor can be controlled, and process control requirements are low. The reverse conducting insulated gate bipolar transistor has the advantages of low manufacturing process control requirements and low manufacturing difficulty.