Manufacturing method of liquid crystal display panel, liquid crystal display panel and display device

The invention provides a manufacturing method of a liquid crystal display panel. The method includes the steps of providing a thin film transistor substrate and an opposite substrate, forming a first photo-alignment layer on the opposite substrate, conducting photo-alignment on the first photo-alignment layer, forming frame rubber to assemble the thin film transistor substrate and the opposite substrate, and packaging liquid crystals, wherein the end, close to the opposite substrate, of the frame rubber is directly arranged on the first photo-alignment layer. The invention further provides the liquid crystal display panel and a display device. In the manufacturing method of the liquid crystal display panel, a flattened layer cannot be damaged by ultraviolet light irradiation during photo-alignment, and therefore good bonding strength is achieved between the thin film transistor substrate and the opposite substrate, and the stability of the liquid crystal display panel is higher.