An image forming apparatus comprising: an image holding member in which a toner image is formed; a transfer member configured to transfer the toner image to a transfer material; a cleaning unit configured to remove waste toner remaining on the transfer member; a waste toner receiving member configured to receive the waste toner removed by the cleaning unit; and a full state detection unit comprising a waste toner amount detection unit disposed in the waste toner receiving member to detect an amount of waste toner and configured to detect whether the waste toner is fully filled in the waste toner receiving member by using the waste toner amount detection unit, wherein the waste toner amount detection unit is movable in a buried state in which the waste toner amount detection unit is positioned under a surface of the waste toner received in the waste toner receiving member, in a non-buried state in which the waste toner amount detection unit is positioned above the surface of the waste toner, and in a loaded state in which the waste toner amount detection unit contacts the surface of the waste toner, the full state detection unit detects whether the waste toner is fully filled in the waste toner receiving member when the waste toner amount detection unit is positioned in the loaded state switched from the non-buried state, characterised in that the transfer member is movable in an away state in which the transfer member is spaced apart by a predetermined distance from the image holding member and in a close state in which the transfer member is closer to the image holding member than in the away state, and the waste toner amount detection unit is configured to switch to the buried state, the non-buried state, or the loaded state in cooperation with movement of the transfer member. an image holding member in which a toner image is formed; a transfer member configured to transfer the toner image to a transfer material; a cleaning unit configured to remove waste toner remaining on the transfer member; a waste toner receiving member configured to receive the waste toner removed by the cleaning unit; and a full state detection unit comprising a waste toner amount detection unit disposed in the waste toner receiving member to detect an amount of waste toner and configured to detect whether the waste toner is fully filled in the waste toner receiving member by using the waste toner amount detection unit, wherein the waste toner amount detection unit is movable in a buried state in which the waste toner amount detection unit is positioned under a surface of the waste toner received in the waste toner receiving member, in a non-buried state in which the waste toner amount detection unit is positioned above the surface of the waste toner, and in a loaded state in which the waste toner amount detection unit contacts the surface of the waste toner, the full state detection unit detects whether the waste toner is fully filled in the waste toner receiving member when the waste toner amount detection unit is positioned in the loaded state switched from the non-buried state, characterised in that the transfer member is movable in an away state in which the transfer member is spaced apart by a predetermined distance from the image holding member and in a close state in which the transfer member is closer to the image holding member than in the away state, and the waste toner amount detection unit is configured to switch to the buried state, the non-buried state, or the loaded state in cooperation with movement of the transfer member.