According to one embodiment, a pattern formation method includes preparing a mask pattern for interference, producing Talbot interference, and forming a pattern by blocking a part of interference light. The mask pattern for interference is arranged periodically a plurality of light transmissive portions. The Talbot interference is based on a transmitted light. The transmitted light is transmitted through the light transmissive portions by applying a light to the mask pattern for interference. The part of interference light is produced by the Talbot interference by means of a mask pattern for light blocking and applying another part of the interference light transmitted through the mask pattern for light blocking to an exposure object member.