In one embodiment, a method for forming pattern includes forming a guide layer on a substrate, forming a copolymer layer of a high-molecular block copolymer on the guide layer; and forming a phase-separation structure with a phase-separation cycle d by self-assembling the copolymer layer. The high-molecular block copolymer includes a first and a second polymer. The guide layer includes a first and a second region disposed on the substrate. Widths of the first and second region respectively are approximately (d/2)×n and (d/2)×m. Both of the first and second region are to be pinned with none of the first and second polymer. Surface energies of the first and second region are different from one another. Integers n and m are odd numbers. Value d is a phase-separation cycle of the high-molecular block copolymer.