Display screen and preparation method thereof

The invention provides a display screen and a preparation method thereof. The display screen comprises a driving substrate, a first substrate and a second substrate, the pixel defining layer is arranged on one side of the driving substrate, and the pixel defining layer comprises a plurality of pixel openings which are arranged at intervals; the cathode wiring layer is arranged on the side, away from the driving substrate, of the pixel defining layer and exposes the pixel opening; the plurality of sub-pixels are arranged at intervals, and each sub-pixel is arranged in the corresponding pixel opening; each sub-pixel comprises a light-emitting part and a light-emitting part, wherein the light-emitting part is arranged in the corresponding pixel opening; the cathode unit is arranged on the side, away from the driving substrate, of the light-emitting part, covers the side wall of the pixel opening and extends out of the pixel opening to be connected with the cathode wiring layer; the projection of the cathode wiri