An extrusion die comprising: an opening for supplying a molten resin; a plurality of die hole portions for discharging a strand made of the molten resin; a resin flow path portion extending in a flow path direction that leads to the plurality of die hole portions from the opening, wherein the resin flow path portion has a resin introduction portion connecting with the opening, and a slit portion located on a downstream side of the resin introduction portion; and a moving plate movable in an up-and-down direction so as to protrude toward the resin flow path portion, wherein the moving plate is arranged along a first direction orthogonal to each of the flow path direction and the up-and-down direction, both end portions of the moving plate in the first direction in an up-and-down direction so as to contact with an inner wall of the resin flow path portion, and a protrusion amount of the moving plate with respect to the resin flow path portion decreases from a central portion in the first direction toward the both end portions, and the plurality of die hole portions are coupled to a downstream-side end portion of the slit portion, the first direction is a width direction of the slit portion, and the moving plate is protruding toward the entire width of the slit portion in a middle of the slit portion, a width - of the resin introduction portion gradually increases from an upstream side toward a downstream side, characterized in that a width of the slit portion is larger than a width of the opening, in that the moving plate is protruding toward the slit portion so that a tip surface of the moving plate becomes lower than an upper surface of the slit portion, and in that the tip surface of the moving plate has a shape in which a height position gradually increases from a center point toward both ends in the first direction. an opening for supplying a molten resin; a plurality of die hole portions for discharging a strand made of the molten resin; a resin flow path portion extending in a flow path direction that leads to the plurality of die hole portions from the opening, wherein the resin flow path portion has a resin introduction portion connecting with the opening, and a slit portion located on a downstream side of the resin introduction portion; and a moving plate movable in an up-and-down direction so as to protrude toward the resin flow path portion, wherein the moving plate is arranged along a first direction orthogonal to each of the flow path direction and the up-and-down direction, both end portions of the moving plate in the first direction in an up-and-down direction so as to contact with an inner wall of the resin flow path portion, and a protrusion amount of the moving plate with respect to the resin flow path portion decreases from a central portion in the first direction toward the both end portions, and the plurality of die hole portions are coupled to a downstream-side end portion of the slit portion, the first direction is a width direction of the slit portion, and the moving plate is protruding toward the entire width of the slit portion in a middle of the slit portion, a width - of the resin introduction portion gradually increases from an upstream side toward a downstream side, characterized in that a width of the slit portion is larger than a width of the opening, in that the moving plate is protruding toward the slit portion so that a tip surface of the moving plate becomes lower than an upper surface of the slit portion, and in that the tip surface of the moving plate has a shape in which a height position gradually increases from a center point toward both ends in the first direction.