The invention discloses an alignment method of a liquid crystal display panel including the following steps: assembling a color filter substrate, an array substrate and a liquid crystal layer into a liquid crystal display panel; applying a first alignment voltage to a common electrode line layer of the array substrate, applying a second alignment voltage to a common electrode layer of the color filter substrate, and a predetermined voltage difference existed between the first alignment voltage and the second alignment voltage; performing alignment to the liquid crystal layer of the liquid crystal display panel by the predetermined voltage difference, to make liquid crystal molecules in the liquid crystal layer arranged with a preset tilt angle; and irradiating the liquid crystal layer with an ultraviolet ray. The effect of alignment can be improved, the dependence of liquid crystal alignment on the data line can be reduced, and improves the product yield.