A method for producing an extrusion die which is employed to extrude a ceramic honeycomb structure for use as a catalyst carrier or support for purifying exhaust gases of an automobile or the like, is disclosed. The method comprises the steps of preparing a first and a second metallic block, forming a plurality of discrete feed passages in the first metallic block, forming a grid network of pooling slots from one end surface of the first metallic block or one end surface of the second metallic block, forming a grid network of extrusion slots from one end surface of the second metallic block towards the other opposed end surface thereof to such a depth as to leave an unopened portion along the other opposed end surface of the second metallic block, joining the one end surface of the first metallic block to the one end surface of the second metallic block so that the feed passages, the pooling slots and the extrusion slots are interconnected in order, and removing the unopened portion from the second metallic block so that the extrusion slots are opened.