The image forming apparatus configured such that a primarily-transferred toner image is secondarily transferred onto a recording material at a secondary transfer portion formed between a transfer belt and a secondary transfer roller, includes a belt unit configured to support the transfer belt in a rotatable manner; and a sheet feeding unit configured to feed the recording material toward the secondary transfer portion. Both the belt unit and the sheet feeding unit are positioned and fixed on the same main stay, so that higher printing accuracy is achieved in consideration of a mutual positional relationship between the sheet feeding portion and the image forming portion.