A method for forming patterns is provided in the present invention. The process includes the steps of using a first mask to perform a first exposure process to a photoresist, using a second mask to perform a second exposure process to the photoresist, wherein the corners of the second opening patterns in the second mask and the corners of the first opening patterns in the first mask overlap each other, and performing a development process to remove the unexposed portions of the photoresist in the two exposure processes to form staggered hole patterns therein.