A honeycomb filter comprising: a plurality of cells as exhaust gas passages, the cells including exhaust gas introduction cells and exhaust gas emission cells; and porous cell walls defining the plurality of cells, the exhaust gas introduction cells each having an open end at an exhaust gas inlet side and a plugged end at an exhaust gas outlet side, the exhaust gas emission cells each having an open end at the exhaust gas outlet side and a plugged end at the exhaust gas inlet side, the exhaust gas introduction cells and the exhaust gas emission cells each having a uniform cross-sectional shape throughout from the end at the exhaust gas inlet side to the end at the exhaust gas outlet side excluding the plugged portion in a direction perpendicular to the longitudinal direction of the cells, wherein in a cross-sectional view perpendicular to the longitudinal direction of the cell, the cross-sectional figure of each of the exhaust gas introduction cells defined by the inner walls thereof is congruent at any cross section from the exhaust gas inlet end to the exhaust gas outlet end, wherein in a cross-sectional view perpendicular to the longitudinal direction of the cell, the cross-sectional figure of each of the exhaust gas emission cells defined by the inner walls thereof is congruent at any cross section from the exhaust gas inlet end to the exhaust gas outlet end; wherein each exhaust gas emission cell is adjacently surrounded fully by the exhaust gas introduction cells across the porous cell walls, the exhaust gas introduction cells including first exhaust gas introduction cells and second exhaust gas introduction cells having a larger cross-sectional area than the first exhaust gas introduction cells in a direction perpendicular to the longitudinal direction of the cells; the cross-sectional area of each exhaust gas emission cell in a direction perpendicular to the longitudinal direction of the cell is equal to or larger than that of each second exhaust gas introduction cell in a direction perpendicular to the longitudinal direction of the cell; and the exhaust gas introduction cells and the exhaust gas emission cells in the cross section perpendicular to the longitudinal direction of the cells are all polygonal, and a side facing the exhaust gas emission cell among sides forming the cross-sectional shape of each first exhaust gas introduction cell is longer than a side facing the exhaust gas emission cell among sides forming the cross-sectional shape of each second exhaust gas introduction cell. a plurality of cells as exhaust gas passages, the cells including exhaust gas introduction cells and exhaust gas emission cells; and porous cell walls defining the plurality of cells, the exhaust gas introduction cells each having an open end at an exhaust gas inlet side and a plugged end at an exhaust gas outlet side, the exhaust gas emission cells each having an open end at the exhaust gas outlet side and a plugged end at the exhaust gas inlet side, the exhaust gas introduction cells and the exhaust gas emission cells each having a uniform cross-sectional shape throughout from the end at the exhaust gas inlet side to the end at the exhaust gas outlet side excluding the plugged portion in a direction perpendicular to the longitudinal direction of the cells, wherein in a cross-sectional view perpendicular to the longitudinal direction of the cell, the cross-sectional figure of each of the exhaust gas introduction cells defined by the inner walls thereof is congruent at any cross section from the exhaust gas inlet end to the exhaust gas outlet end, wherein in a cross-sectional view perpendicular to the longitudinal direction of the cell, the cross-sectional figure of each of the exhaust gas emission cells defined by the inner walls thereof is congruent at any cross section from the exhaust gas inlet end to the exhaust gas outlet end; wherein in a cross-sectional view perpendicular to the longitudinal direction of the cell, the cross-sectional figure of each of the exhaust gas introduction cells defined by the inner walls thereof is congruent at any cross section from the exhaust gas inlet end to the exhaust gas outlet end, wherein in a cross-sectional view perpendicular to the longitudinal direction of the cell, the cross-sectional figure of each of the exhaust gas emission cells defined by the inner walls thereof is congruent at any cross section from the exhaust gas inlet end to the exhaust gas outlet end; wherein each exhaust gas emission cell is adjacently surrounded fully by the exhaust gas introduction cells across the porous cell walls, the exhaust gas introduction cells including first exhaust gas introduction cells and second exhaust gas introduction cells having a larger cross-sectional area than the first exhaust gas introduction cells in a direction perpendicular to the longitudinal direction of the cells; the cross-sectional area of each exhaust gas emission cell in a direction perpendicular to the longitudinal direction of the cell is equal to or larger than that of each second exhaust gas introduction cell in a direction perpendicular to the longitudinal direction of the cell; and the exhaust gas introduction cells and the exhaust gas emission cells in the cross section perpendicular to the longitudinal direction of the cells are all polygonal, and a side facing the exhaust gas emission cell among sides forming the cross-sectional shape of each first exhaust gas introduction cell is longer than a side facing the exhaust gas emission cell among sides forming the cross-sectional shape of each second exhaust gas introduction cell.