An electric field and discharge generator includes an upper frame (1), a lower frame (8), a discharge electrode (2), and a counter electrode (7). The upper frame (1) has an opening (1a) for introducing outside air inside. The lower frame (8) has an opening (8a) for exhausting inside air outside. The discharge electrode (2) has a plate-like shape and is so disposed that it is perpendicular to an opening surface of the upper frame (1) and an opening surface of the lower frame (8). The counter electrode (7) has an electrode portion (7a) having a plate-like shape. The electrode portion (7a) is obliquely disposed with respect to the opening surface of the upper frame (1) and the opening surface of the lower frame (8).