In a method for manufacturing an array substrate, a first photoresist pattern is formed on a buffer layer of a non-display region and the buffer layer uncovered by the first photoresist pattern is removed to form a first via hole in the non-display region. A second via hole is formed on the basis of the first via hole. The second via hole is connected to the first via hole. By forming the first via hole in the non-display region and forming the second via hole on the basis of the first via hole, completeness of film layers is ensured and product yield is improved.