Disclosed is a method of manufacturing a tablet (6) by press-forming powder in a mortar (1) using a pushing surface (9a) at the lower end of an upper pounder and a pushing surface (11a) at the upper end of a lower pounder. Concave forming grooves (2a) integrally linked to the upper and lower pushing surfaces (9a, 11a) are formed in the inner circumferential surfaces of mortar holes (2). The mortar can be divided into upper separable piece (7) and a lower separable piece (8) at the bottom portions of the forming grooves (2a). After a final fixed pounder, which is one of the upper and lower pounders, is fixed at a press-forming position at which the pushing surface (9a or 11a) is integrally linked to the corresponding forming groove (2a), a final pressing pounder, which is the other pounder, is moved to the press-forming position so that the tablet (6) is press-formed. When the tablet (6) is taken out of the mortar by separating the upper and lower separable pieces (7, 8), the tablet is taken out of a final fixed separable piece, which is the separable piece (7 or 8) adjacent to the final fixed pounder, and the final fixed pounder. Subsequently, the tablet is taken out of a final pressing separable piece, which is the separable piece (7 or 8) adjacent to the final pressing pounder.