A composition for pattern formation includes a block copolymer and a solvent. The block copolymer is capable of forming a phase separation structure through directed self-assembly. The block copolymer includes a first block and a second block. The first block includes a first repeating unit which includes at least two silicon atoms. The second block includes a second repeating unit which does not include a silicon atom. A sum of the atomic weight of atoms constituting the first repeating unit is no greater than 700.