A pattern forming method includes: a modification treatment step of, in accordance with a pattern to be formed on a pattern forming surface of a base body, applying a light beam having a width smaller than a diameter of each of dots to constitute the pattern, onto a treatment target region including at least outer edges on both sides in a width direction of a region where the pattern is to be formed in the pattern forming surface, thereby carrying out modification treatment on the treatment target region; and a droplet deposition step of ejecting and depositing droplets of a functional liquid by an inkjet method onto the region where the pattern is to be formed including the treatment target region where the modification treatment has been carried out.