An image forming apparatus includes a placement tray, an image forming unit, a drive unit, a control substrate, a power supply substrate, a high-voltage substrate, and low-voltage power supply harnesses. The placement tray holds a recording sheet thereon. The image forming unit forms an image on the recording sheet. The drive unit supplies driving force to the image forming unit. The control substrate controls the drive unit. The power supply substrate supplies electric power to the control substrate. The high-voltage substrate is disposed in one side of the placement tray. In the high-voltage substrate, voltage is generated higher than voltage in the power supply substrate. The low-voltage power supply harnesses are disposed in another side of the placement tray so as to supply electric power from the power supply substrate to the control substrate.