The invention discloses a display panel, a manufacturing method thereof and a display device. In the display panel, liquid crystal molecules in a liquid crystal layer and in a region corresponding to each pixel are in a polymer network shape, and as the distance between the pixel and a light source in a lateral incoming light source module is larger, the area occupied by the polymer network formed through a photopolymerization reaction with the liquid crystal molecules in the region corresponding to each pixel is larger; in this way, when voltage is applied to each pixel, the outgoing light area of scattered light is larger and the outgoing light amount is larger due to disordered orientation caused by influence of the polymer network when the liquid crystal molecules in the region corresponding to the pixel farther away from the light source deflect, so that the problem that light introduced into the pixel region is less as the distance between the pixel and the light source is larger because of the lateral incoming light source module is solved. In this circumstance, the outgoing light amount of each pixel is controlled through adjustment of the effective outgoing light area of each pixel, and the uniformity of display brightness of the display panel can be effectively improved.