A honeycomb structured body of the present invention is configured by
assembling one or at least two pillar-shaped porous ceramic member in
which a number of through holes are longitudinally placed in parallel
with one another with a partition wall therebetween, either one of ends
of these through holes being sealed, wherein the porous ceramic member is
a composite made of ceramic particles and silicon, and a catalyst is
supported on the partition wall, and a relationship between an aperture
ratio .alpha. (%) of the honeycomb structured body and an supported
amount .beta. (g/L) of the catalyst satisfies the following inequality
(1): 9.8-0.125.times..alpha..ltoreq..beta. (1).