The exhaust gas purification device according to the present invention is provided with a wall flow structure substrate that has an entry-side cell, an exit-side cell and a porous partition 16, first catalyst parts 20 which are formed in small pores 18a having a relatively small pore diameter among internal pores in the partition 16, and second catalyst parts 30 which are formed in large pores 18b having a relatively large pore diameter among the internal pores in the partition 16. The first catalyst parts 20 and the second catalyst parts 30 each contain a carrier and at least one type of noble metal from among Pt, Pd and Rh supported on the carrier. The noble metal content in the first catalyst parts 20 is smaller than the noble metal content in the second catalyst parts 30 per 1 liter of substrate volume.