A honeycomb structured body includes a plurality of honeycomb members which are bonded to one another by interposing an adhesive layer. Each of the honeycomb members has a number of cells placed in parallel with one another in the longitudinal direction with a cell wall therebetween. When the longitudinal direction is defined as the orientation axis, the degree of orientation Ω of the inorganic fibers in the adhesive layer obtained by the Saltykov method is set in the range of about 0.2≦Ω≦about 0.7 or in the range of about −0.7≦Ω≦about −0.2 in the adhesive layer.