A method for manufacturing an absorbent body comprising: pulverizing to produce a fibrous pulp that is to serve as a material of an absorbent body, by using a feed roller to feed a pulp sheet toward a pulverizer in a feeding direction while supporting the pulp sheet from one end to another end in a width direction of the pulp sheet, and pulverizing the fed pulp sheet by successively shredding a leading end of the pulp sheet with use of a plurality of moving pulverizing blades of the pulverizer; cutting to cut a leading end portion (CLp) of a preceding pulp sheet and a leading end portion (CLf) of a new following pulp sheet; and joining to produce a jointed pulp sheet by joining the preceding pulp sheet and the following pulp sheet with use of a joint material, in the pulverizing, the jointed pulp sheet fed with the feed roller being pulverized in order of first the preceding pulp sheet and then the following pulp sheet, in the cutting, the leading end portion (CLp) of the preceding pulp sheet and the leading end portion (CLf) of the new following pulp sheet being diagonally cut such that a diagonal cut line of the leading end portion (CLp) and a diagonal cut line of the leading end portion (CLf) have the same inclination, and such that Condition 1 shown below is satisfied with respect to the inclination, and in the joining, the preceding pulp sheet and the following pulp sheet being joined with use of the joint material in a state where the diagonal cut line of the leading end portion (CLp) and the diagonal cut line of the leading end portion (CLf) have been brought together, Condition 1: the length (La) of the diagonal cut lines in the feeding direction > a shortest distance (Lb) from a support position, at which the feed roller supports the pulp sheet, to a movement locus of blade tips of the pulverizing blades. pulverizing to produce a fibrous pulp that is to serve as a material of an absorbent body, by using a feed roller to feed a pulp sheet toward a pulverizer in a feeding direction while supporting the pulp sheet from one end to another end in a width direction of the pulp sheet, and pulverizing the fed pulp sheet by successively shredding a leading end of the pulp sheet with use of a plurality of moving pulverizing blades of the pulverizer; cutting to cut a leading end portion (CLp) of a preceding pulp sheet and a leading end portion (CLf) of a new following pulp sheet; and joining to produce a jointed pulp sheet by joining the preceding pulp sheet and the following pulp sheet with use of a joint material, in the pulverizing, the jointed pulp sheet fed with the feed roller being pulverized in order of first the preceding pulp sheet and then the following pulp sheet, in the cutting, the leading end portion (CLp) of the preceding pulp sheet and the leading end portion (CLf) of the new following pulp sheet being diagonally cut such that a diagonal cut line of the leading end portion (CLp) and a diagonal cut line of the leading end portion (CLf) have the same inclination, and such that Condition 1 shown below is satisfied with respect to the inclination, and in the joining, the preceding pulp sheet and the following pulp sheet being joined with use of the joint material in a state where the diagonal cut line of the leading end portion (CLp) and the diagonal cut line of the leading end portion (CLf) have been brought together, Condition 1: the length (La) of the diagonal cut lines in the feeding direction > a shortest distance (Lb) from a support position, at which the feed roller supports the pulp sheet, to a movement locus of blade tips of the pulverizing blades.