A method for manufacturing an absorbent body includes: pulverizing to produce a fibrous pulp that is to serve as a material of an absorbent body, by pulverizing a leading end of a pulp sheet (1)； cutting to cut a preceding pulp sheet (1p) and a following pulp sheet (1f)； and joining to produce a jointed pulp sheet by joining the preceding pulp sheet (1p) and the following pulp sheet (1f), the jointed pulp sheet being pulverized in order of first the preceding pulp sheet (1p) and then the following pulp sheet (1f), the method includes cutting to diagonally cut the preceding pulp sheet (1p) and the following pulp sheet (1f) to have the same inclination, and such that the length (La) of the diagonal cut lines in the feeding direction is longer than a shortest distance (Lb) from a support position (20a) to a movement locus of blade tips of pulverizing blades (31b), and joining to produce a jointed pulp sheet by joining the preceding pulp sheet and the following pulp sheet in a state where the diagonal cut line of the trailing end portion (CLp) and the diagonal cut line of the leading end portion (CLf) have been brought together.
