A composition for pattern formation includes a block copolymer. The block polymer includes a first labile group at an end of a main chain of the block copolymer. The first acid liable group is capable of being dissociated by an acid or heat. The composition preferably further contains an acid generator that generates an acid upon application of an energy. The block copolymer is preferably capable of forming a phase separation structure through directed self-assembly. The first labile group is preferably represented by formula (a). R represents a monovalent organic group having 1 to 20 carbon atoms; R′ represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; and * denotes a binding site to an atom at the end of the main chain of the block copolymer.