A powder compaction mold comprising a die and upper and lower punches configured to fit into the die, the powder compaction mold being configured to compress a powder between the upper and lower punches to manufacture a powder compact, wherein, of the members forming the powder compaction mold , at least one of two members in sliding contact with each other has therein a vent passage through which gas is vented from a filling space for the powder surrounded by the die and the lower punch to an outside of the powder compaction mold , and wherein the vent passage has a gas intake port that is open to a clearance section formed between the two members and connecting to the filling space, characterized in that the lower punch comprises a plurality of punch segments formed as hollow members, the plurality of punch segments comprising a first punch segment , a second punch segment and a third punch segment , wherein the vent passage is formed in at least one of the punch segments, wherein the powder compaction mold further comprising a core rod extending through the center of the lower punch , wherein the plurality of punch segments are arranged coaxially with the core rod , wherein the powder compaction mold has clearance sections formed between the inner peripheral surface of the die and the outer peripheral surface of the first punch segment , between the inner peripheral surface of the first punch segment and the outer peripheral surface of the second punch segment , between the inner peripheral surface of the second punch segment and the outer peripheral surface of the third punch segment , and between the inner peripheral surface of the third punch segment and the outer peripheral surface of the core rod , wherein the vent passage is formed in the first punch segment , which is the radially outermost segment of the lower punch , and the vent passage includes an axial passage , a radial passage extending toward the inner peripheral surface of the die, and a radial passage extending toward the outer peripheral surface of the second punch segment . wherein, of the members forming the powder compaction mold , at least one of two members in sliding contact with each other has therein a vent passage through which gas is vented from a filling space for the powder surrounded by the die and the lower punch to an outside of the powder compaction mold , and wherein the vent passage has a gas intake port that is open to a clearance section formed between the two members and connecting to the filling space, characterized in that the lower punch comprises a plurality of punch segments formed as hollow members, the plurality of punch segments comprising a first punch segment , a second punch segment and a third punch segment , wherein the vent passage is formed in at least one of the punch segments, wherein the powder compaction mold further comprising a core rod extending through the center of the lower punch , wherein the plurality of punch segments are arranged coaxially with the core rod , wherein the powder compaction mold has clearance sections formed between the inner peripheral surface of the die and the outer peripheral surface of the first punch segment , between the inner peripheral surface of the first punch segment and the outer peripheral surface of the second punch segment , between the inner peripheral surface of the second punch segment and the outer peripheral surface of the third punch segment , and between the inner peripheral surface of the third punch segment and the outer peripheral surface of the core rod , wherein the vent passage is formed in the first punch segment , which is the radially outermost segment of the lower punch , and the vent passage includes an axial passage , a radial passage extending toward the inner peripheral surface of the die, and a radial passage extending toward the outer peripheral surface of the second punch segment . <EOS>