An image forming apparatus including a first unit having an image bearing member, a second unit having a development member, an apparatus main body which includes an opening portion, an opening-closing member to open or close the opening portion, a first portion contacting with a part of the first unit to position the first unit to the apparatus main body, and a second portion arranged on an opposite side of the first portion with respect to the image bearing member, and a sandwiched unit movable between a first position at which the sandwiched unit is sandwiched between the first unit and the second portion and a second position at which the sandwiched unit is not sandwiched, wherein when the sandwiched unit is located at the first position, a part of the first unit is urged against the first portion by the sandwiched unit.