A pillar-shaped honeycomb structure including a plurality of first cells extending from an inlet side end surface to an outlet side end surface, and a plurality of second cells extending from the inlet side end surface to the outlet side end surface, with a porous partition wall interposed therebetween, wherein a porous film having a porosity higher than that of the partition walls is provided on a surface of each of the first cells, and at a cross-section orthogonal to the direction in which the first cells of the pillar-shaped honeycomb structure filter extend, the average thickness of the porous film in the central portion is larger than the average thickness of the porous film in the outer peripheral portion.