The invention provides an array substrate, a preparation method of the array substrate, a liquid crystal display panel, and a display device. The problem of large parasitic capacitance caused by overlapping grid lines and data lines can be avoided. The array substrate includes a substrate, a plurality of grid lines, a plurality of data lines, and a plurality of common electrode lines are arrangedon the substrate; the grid lines and the data lines are parallel, and the common electrode lines intersect with the grid lines; the common electrode lines are insulated from one another; the grid lines and/or the data lines and the common electrode lines define a plurality of sub-pixel areas, and the sub-pixel areas are provided with one or more thin film transistors and pixel electrodes; the pixel electrodes and the common electrode lines are at the same layer and made of the same material; each thin film transistor includes a grid, a semiconductor active pattern, a source electrode, and a drain electrode; the source electrodes of the thin film transistors are electrically connected with the data lines, the drain electrodes are electrically connected with the pixel electrodes, and the grid is electrically connected with the grid lines.