A plasma processing device member according to the disclosure includes a base material and a film formed of an oxide, or fluoride, or oxyfluoride, or nitride of a rare-earth element, the film being disposed on at least part of the base material, the film including a surface to be exposed to plasma, the surface having an area occupancy of open pores of 8% by area or more, and an average diameter of open pores of 8 μm or less.