A discharge unit comprising: a discharge electrode; a counter electrode; and a voltage supply section configured to give a potential difference between the discharge electrode and the counter electrode, wherein the discharge unit includes a resin-made insulating member which supports the discharge electrode and the counter electrode, the discharge electrode is configured as a metal material and includes: a plate-like electrode support plate; and a plurality of discharge sections (73, 74) arranged along, and supported at, a side edge portion of the electrode support plate so as to be opposed to the counter electrode, and the insulating member includes a support which supports only a middle region of the electrode support plate between two outermost discharge sections (73a, 74a) of the plurality of discharge sections (73,74); a fixing member which supports the discharge electrode by sandwiching the middle region of the electrode support plate between the fixing member and the insulating member; and the fixing member is made of a conductive member having a flanged portion, the flanged portion being arranged opposite the counter electrode with the discharge sections (73, 74) interposed there between and covering the entire discharge sections (73,74), being electrically connected to the discharge sections (73, 74) and having a shape along the discharge sections (73, 74). a counter electrode; and a voltage supply section configured to give a potential difference between the discharge electrode and the counter electrode, wherein the discharge unit includes a resin-made insulating member which supports the discharge electrode and the counter electrode, the discharge electrode is configured as a metal material and includes: a plate-like electrode support plate; and a plurality of discharge sections (73, 74) arranged along, and supported at, a side edge portion of the electrode support plate so as to be opposed to the counter electrode, and the insulating member includes a support which supports only a middle region of the electrode support plate between two outermost discharge sections (73a, 74a) of the plurality of discharge sections (73,74); a fixing member which supports the discharge electrode by sandwiching the middle region of the electrode support plate between the fixing member and the insulating member; and a plate-like electrode support plate; and a plurality of discharge sections (73, 74) arranged along, and supported at, a side edge portion of the electrode support plate so as to be opposed to the counter electrode, and the insulating member includes a support which supports only a middle region of the electrode support plate between two outermost discharge sections (73a, 74a) of the plurality of discharge sections (73,74); a fixing member which supports the discharge electrode by sandwiching the middle region of the electrode support plate between the fixing member and the insulating member; and the fixing member is made of a conductive member having a flanged portion, the flanged portion being arranged opposite the counter electrode with the discharge sections (73, 74) interposed there between and covering the entire discharge sections (73,74), being electrically connected to the discharge sections (73, 74) and having a shape along the discharge sections (73, 74).