The present disclosure provides a display panel and a method for preparing same, and a display device. The preparation method includes steps of: providing a base plate, wherein the base plate includes a display area and a binding area, and a magnetic composite structure is disposed in the base plate; disposing a magnetic probe at a position on a side of the base plate that corresponds to the binding area; and adding droplets to an upper surface of the base plate, and controlling the magnetic probe to be turned on, so as to form an alignment film having a uniform thickness on the upper surface of the base plate.