D column lower joint assembly

The utility model provides a D column lower joint assembly which is used in a vehicle and comprises a rear side wall outer plate, a rear end plate welding assembly, a rear side wall inner plate welding assembly and a D column outer plate assembly. Wherein the rear side wall outer plate is fixedly connected to the outer side part of the rear side wall inner plate welding assembly so as to form a complete rear side wall structure. A lightening hole is formed in the lower portion of the rear side wall inner plate welding assembly and used for lightening the weight of a vehicle body. The D column outer plate assembly is fixedly connected to the rear portion of the rear side wall outer plate. And the rear end plate welding assembly is connected to the lower part of the D column outer plate assembly. A first reinforcing device is arranged on the inner side of the D-column outer plate assembly, and the first reinforcing device is connected to the rounded corner position of the tail door frame and used for improving