Particulate filter provided in the exhaust gas purification device includes: a wall-flow part having an inlet-side cell that is open only at an end on an exhaust gas inflow side, outlet-side cell adjacent to this inlet-side cell and is open only at an end on an exhaust gas outflow side, a porous wall partitions the inlet-side cell from the outlet-side cell; a straight-flow part having a through cell that penetrates the filter in axial direction and is open at the end on the exhaust gas inflow side as well as the end on the exhaust gas outflow side. In a cross section of the filter orthogonal to its axial direction, cross-sectional areas of the inlet-side cell and outlet-side cell present in an outer peripheral region of the cross section are larger than cross-sectional areas of the inlet-side cells and the outlet-side cell in a central region of the cross section.