A method for manufacturing an array substrate includes: forming a strip-shaped barrier wall(s) on a base substrate, wherein the width of each barrier wall is less than or equal to a distance between a first metal trace to be formed and a second metal trace to be formed; and forming a first metal trace at one side of each barrier wall located in a direction perpendicular to an extending direction of the barrier wall, and forming a second metal trace at an opposite side of the barrier wall located in the direction perpendicular to the extending direction of the barrier wall.