Disclosed are a display panel and a preparation method thereof, and a display device. The display panel includes a display area and a peripheral area surrounding display area; display area includes a light emitting device, peripheral area includes a retaining wall, and display and peripheral area include a encapsulation structure covering retaining wall and light emitting device; encapsulation structure includes: a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer in sequence; first and second inorganic encapsulation layers cover display and peripheral area; organic encapsulation layer covers display area and at least part of peripheral area, and there is a gap between organic encapsulation layer and retaining wall; organic encapsulation layer and first inorganic encapsulation layer includes a middle contact surface and a peripheral contact surface surrounding middle contact surface, surface energy of middle contact surface is greater than that of peripheral contact surface.