The invention provides a liquid crystal lens and a manufacturing method thereof and a display device. The liquid crystal lens comprises a first substrate, a second substrate and a liquid layer betweenthe first substrate and the second substrate. The liquid layer comprises a liquid crystal layer and a filling layer, wherein the liquid crystal layer comprises a plurality of liquid crystal lens units, the liquid crystal units make contact with the first substrate, and the space, except the liquid crystal layer, between the first substrate and the second substrate is filled with the filling layer. The liquid crystal lens further comprises first electrodes and a second electrode, wherein the first electrodes and the second electrode are arranged to form an electric field so as to drive liquidcrystal molecules of the liquid crystal layer to rotate and adjust the curvature of the liquid crystal lens units. By means of the liquid crystal lens, the adjusting range of the focal length of the liquid crystal lens can be greatly expanded.