A honeycomb structured body of the present invention is a honeycomb structured body in which a plurality of porous ceramic members are combined with one another through an adhesive layer, each of the porous ceramic members having a plurality of cells which are allowed to penetrate in a longitudinal direction with a wall portion therebetween and either one end of which is sealed, with a catalyst supporting layer being adhered to the wall portion, wherein, supposing that the rate of the pore volume of pores having a pore diameter of 10 .mu.m or less to the entire pore volume of the porous ceramic member is X.sub.1 (%), the porosity is Y.sub.1 (%) and the weight of the catalyst supporting layer is Z.sub.1 (g/l), these X.sub.1, Y.sub.1 and Z.sub.1 are allowed to satisfy the following expressions (1) and (2): X.sub.1.ltoreq.20-Z.sub.1/10 (1), and Y.sub.1.gtoreq.35+7Z.sub.1/40 (2) (where about 20.ltoreq.Z.sub.1.ltoreq.about 150).