An image forming apparatus comprises a photosensitive drum, a charged wire which extends in a shaft direction of the photosensitive drum and charges the photosensitive drum by electric discharge, a frame disposed so as to surround the charged wire, the frame in which a cover side opening is formed in the side opposite to the photosensitive drum with respect to the charged wire, and a cover member disposed so as to cover the cover side opening while forming a blow path in communication with the cover side opening between the frame and the cover member. The cover member moves along the charged wire and is constructed detachably from a side surface of the frame and also a cleaning member for cleaning the charged wire is disposed.