To provide a brush charging device uniformly charging the surface of a photoreceptor drum by preventing the disturbance of rotation brush hair.

A rotation brush 41 is brought into pressing contact with the surface of the photoreceptor drum 21, the rotation brush 41 and the photoreceptor drum 21 are made to be rotated at the same circumferential speed in the respective arrow directions A, B and, then, the outer periphery of the rotation brush 41 and the outer periphery of the photoreceptor drum 21 are moved at the same speed in the same direction on the contact part between the rotation brush 41 and the photoreceptor drum 21. The inclination of the hair of the rotation brush 41 is set so as to take a direction along the rotation direction of the surface of the photoreceptor drum 21. Therefore, the hair of the rotation brush 41 is always aligned in the peripheral direction, the disturbance of hair alignment is not reflected as the irregularity of charging of the surface of the photoreceptor drum 21 and the surface of the photoreceptor drum 21 is uniformly charged.