A charged particle beam exposure method capable of suppressing the degradation of dimensional accuracy of exposed pattern elements due to the proximity effect and Coulomb effect defocusing. The charged particle beam exposure method is a method in which a charged particle beam is irradiated to a mask to transfer an image of a pattern formed on the mask onto a radiation-sensitive substrate. The method includes dividing one exposed pattern element which is to be formed on the radiation-sensitive substrate into a plurality of regions including a region lying at a marginal portion of the exposed pattern element and at least one other region lying inside the marginal portion, and forming patterns respectively corresponding to the regions on the mask, and further adjusting, when the patterns are to be transferred onto the radiation-sensitive substrate, the transfer positions of images of the patterns corresponding to the regions so that the divided regions are combined together to form the exposed pattern element on the radiation-sensitive substrate.