In a honeycomb filter in which a plurality of cells are formed by porous
partition walls, and a predetermined cell whose one end portion is
plugged, and a remaining cell whose other end portion is plugged are
alternately arranged in such a manner as to form checked patterns in the
opposite end portions. In a section of the filter, a sectional area of
the predetermined cell is different from that of the remaining cell, a
value of a ratio of a channel hydraulic diameter of the cell having a
large sectional area to that of the cell having a small sectional area is
1.2 or more, at least a sectional shape of the cell having the large
sectional area is a quadrangular shape whose portion corresponding to at
least one corner portion is circular, and a value of a ratio of minimum
thickness of a portion (intersection portion) in which the partition
walls cross one another to a thickness of each partition wall 2 is 0.7 or
more and less than 1.3. The honeycomb filter is capable of inhibiting a
fluid inflow-side end face (opening of an inflow-side cell) from being
closed by particulates and the like, and maintaining high strength.