A pattern formation method, mask pattern formation method and a method for manufacturing semiconductor devices are provided in this disclosure, which are directed to the field of semiconductor processes. The pattern formation method comprises: providing a substrate; forming a polymer thin film containing a block copolymer on the substrate; forming a first pattern through imprinting the polymer thin film with a stamp; forming domains composed of different copolymer components through directed self assembly of the copolymer in the first pattern; selectively removing the domains composed of copolymer components to form a second pattern. In the embodiments of the present invention, finer pitch patterns can be obtained through combining the imprinting and DSA process without exposure, which as compared to the prior art methods has the advantage of simplicity. Furthermore, stamps used in imprinting may have relative larger pitches, facilitating and simplifying the manufacture and alignment of the stamps.