An image forming apparatus which includes a first image forming portion including a first photosensitive member, a first charging member for electrically charging the first photosensitive member to form an image thereon, and a first cleaning brush for cleaning the first charging member, a second image forming portion including a second photosensitive member, a second charging member for electrically charging the second photosensitive member to form an image thereon, and a second cleaning brush which has a longer brush length than that of the first cleaning brush for cleaning the second charging member, a driven mechanism for causing the first cleaning brush to be rotatably driven by the first charging member which is rotatably driven along with rotation of the first photosensitive member, and a drive coupling mechanism configured to drivably couple the second charging member and the second cleaning brush to transmit a driving force from the second charging member which is rotatably driven along with the rotation of the first photosensitive member to the second cleaning brush.