HONEYCOMB STRUCTURE AND MANUFACTURING METHOD OF HONEYCOMB STRUCTURE

There is disclosed a honeycomb structure in which cracks are not easily generated at canning and during use. The honeycomb structure includes a honeycomb structure part having porous partition walls 5, and porous plugged portions 8, and when in a cross section of each of the plugged portions 8 which is parallel to an extending direction of cells 4 of the honeycomb structure part, there is drawn a straight line as an inner boundary line K1 which is positioned at a distance of 30% of a distance between an outer end surface 11 and an inner end surface 13, from the inner end surface 13 as the end surface on a side opposite to the outer end surface 11 as the end surface on a side of the end surface of the honeycomb structure part, and which is perpendicular to the extending direction of the cells 4, and there is drawn a straight line as an outer boundary line K2 which is positioned at a distance of 70% of the distance between the outer end surface 11 and the inner end surface 13, from the inner end surface 13, and which is perpendicular to the extending direction of the cells 4, each of the plugged portions has an outer region 15 which is the region between the outer end surface 11 and the outer boundary line K2, and an inner region 17 which is the region between the inner end surface 13 and the inner boundary line K1 and whose porosity is larger than a porosity of the outer region 15.