The image forming apparatus includes a sheet storing unit insertably and pullably attached to the frame unit, an image forming unit, and a frame unit. The frame unit includes two frame members parallel to each other with a predetermined distance therebetween and are connected and fixed to each other. The two frame members respectively include engaged portions. The sheet storing unit includes engaging portions respectively engageable with the engaged portions in a state where the sheet storing unit is inserted in the frame unit. In a state where the engaging portions respectively engage with the engaged portions, the engaging portions that respectively engage with the engaged portions and a portion between the two engaging portions of the sheet storing unit serve as strengthening members to regulate deformation of the two frame members by at least a predetermined amount.