Corner profile and window frame profile connecting structure capable of preventing deformation and loosening

The utility model relates to a corner section bar and window frame section bar connecting structure, in particular to a corner section bar and window frame section bar connecting structure capable of preventing deformation and loosening. The connecting structure aims to solve the problem that in the screwing process of a screw in an existing connecting structure for a corner profile and a window frame profile of a plastic-steel door and window, due to deformation of the surface of an extruded profile, the screw is loosened after being used for a period of time. A first thickened boss is arranged on the inner surface of the side, attached to a window frame profile, of a corner profile, a second thickened boss is arranged on the inner surface of the side, attached to the corner profile, of the window frame profile, a first mounting hole penetrating through the inner surface and the outer surface of the corner profile is formed in the first thickened boss, and a nut is coaxially and fixedly embedded in the first