A sheet storage apparatus includes a storage unit configured to store sheets, a biasing unit configured to apply a biasing force to the storage unit so that the storage unit is biased toward a mounting position, and a regulating unit configured to be located at a first position at which movement of the storage unit in a drawing out direction is regulated and a second position at which movement of the storage unit from the mounting position in the drawing out direction is permitted. The regulating unit is moved from the first position to the second position in response to an operation by an operator who operates a handle.