A plugged honeycomb structure (100, 101, 102, 103) comprising: a honeycomb structure section having porous partition walls with which a plurality of cells extending from an inflow side end surface to an outflow side end surface are formed to become through channels of a fluid, the plurality of cells including cells having different open areas in a cross section perpendicular to an extending direction of the cells; inflow side plugged portions arranged in inflow side end portions of predetermined ones of the plurality of cells; and outflow side plugged portions arranged in outflow side end portions of the remaining cells (cells other than the predetermined cells), wherein in the honeycomb structure section, outflow cells which are the cells provided with the inflow side plugged portions and inflow cells which are the cells provided with the outflow side plugged portions are alternately formed via the partition walls, the open area of each of the inflow cells in a central portion of the honeycomb structure section is larger than the open area of each of the outflow cells in the central portion of the honeycomb structure section, and a difference in the open area between the outflow cell and the inflow cell in an outer peripheral portion of the honeycomb structure section is smaller than a difference in the open area between the outflow cell and the inflow cell in the central portion of the honeycomb structure section; and wherein in the outer peripheral portion of the honeycomb structure section, the difference in the open area between the outflow cell and the inflow cell decreases, from a center side toward an outer periphery of the honeycomb structure section; and wherein, when the honeycomb has an integral structure, the outer peripheral portion is a portion in a region from the outer periphery of the cylindrical honeycomb structure section to a position of a length of 30% of a diameter of the honeycomb structure section and when the honeycomb structure section has a shape other than the cylindrical shape, the outer peripheral portion is a portion in a region from the outer periphery of the honeycomb structure section to a position of 40% of the longest diameter. a honeycomb structure section having porous partition walls with which a plurality of cells extending from an inflow side end surface to an outflow side end surface are formed to become through channels of a fluid, the plurality of cells including cells having different open areas in a cross section perpendicular to an extending direction of the cells; inflow side plugged portions arranged in inflow side end portions of predetermined ones of the plurality of cells; and outflow side plugged portions arranged in outflow side end portions of the remaining cells (cells other than the predetermined cells), wherein in the honeycomb structure section, outflow cells which are the cells provided with the inflow side plugged portions and inflow cells which are the cells provided with the outflow side plugged portions are alternately formed via the partition walls, the open area of each of the inflow cells in a central portion of the honeycomb structure section is larger than the open area of each of the outflow cells in the central portion of the honeycomb structure section, and a difference in the open area between the outflow cell and the inflow cell in an outer peripheral portion of the honeycomb structure section is smaller than a difference in the open area between the outflow cell and the inflow cell in the central portion of the honeycomb structure section; and wherein in the outer peripheral portion of the honeycomb structure section, the difference in the open area between the outflow cell and the inflow cell decreases, from a center side toward an outer periphery of the honeycomb structure section; and wherein, when the honeycomb has an integral structure, the outer peripheral portion is a portion in a region from the outer periphery of the cylindrical honeycomb structure section to a position of a length of 30% of a diameter of the honeycomb structure section and when the honeycomb structure section has a shape other than the cylindrical shape, the outer peripheral portion is a portion in a region from the outer periphery of the honeycomb structure section to a position of 40% of the longest diameter.