The present invention relates to a honeycomb catalytic converter including: a honeycomb structured body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween; a noble metal supported on the honeycomb structured body; and an inlet-side end face and on outlet-side end face, wherein each partition wall includes a substrate portion in the form of an extrudate containing a ceria-zirconia complex oxide and alumina, and a coat layer formed on a surface of the substrate portion and containing the noble metal, and the inlet-side end face has a higher aperture ratio than the outlet-side end face.