An image forming apparatus includes an apparatus main body, a drum unit, an intermediate transfer unit, a waste toner container, and a first guide portion. The drum unit includes a photoconductor drum. The intermediate transfer unit includes a transfer belt and a belt cleaning portion. The belt cleaning portion removes waste toner remaining on the transfer belt and conveys the waste toner toward one side in a width direction of the transfer belt. The waste toner container is provided below an end of the drum unit on the one side and includes an introduction port that introduces waste toner to an inside of the waste toner container. The first guide portion guides the waste toner conveyed by the belt cleaning portion to the one side, from the introduction port to the inside of the waste toner container.