Provided is an exhaust gas purification catalyst body that can improve exhaust gas purification performance while maintaining favorable PM collection performance. The exhaust gas purification catalyst body includes a base of a wall flow structure having an inlet side cell, an outlet side cell, and porous partition wall, and a catalyst layer that is formed in the partition wall that is in contact with the inlet side cell or the outlet side cell. The catalyst layer is formed in a region of at least 50% of the thickness of the partition wall from a surface of the partition wall, and held on the surface of internal pores in the partition wall in the region.