A chamber device includes: a chamber body; an anode extending along a Z direction; a cathode disposed in an internal space facing the anode, extending along the Z direction, and including a base part and a discharge part protruding from the base part toward the anode; a cathode-side cover part including a base facing part and covers a part of the base part; a cathode-side acoustic absorbing member disposed in a space between the cathode-side cover part and the base part; and an inclined part including an inclined surface disposed in a space closer to the base part than the base facing part in the V direction and closer to the discharge part than the base facing part in the H direction, broadening to an opposite side with respect to the discharge part as the inclined surface is closer to the base part along the V direction, and extending in the Z direction.