An image forming apparatus comprising: an attachment table to which an object is attachable; a transfer unit configured to transfer an image onto the object; a transport unit configured to transport the attachment table along a transport path that has a transport start position on one side relative to the transfer unit and has a transport end position on a same side as the transport start position relative to the transfer unit, the transport path extending beyond the transfer unit and the attachment table being transported so as to turn back at a position beyond the transfer unit; and a height adjusting unit configured to adjust a height of the attachment table, wherein: the transport unit is configured to transport the attachment table to which the object has been attached to a transfer position of the transfer unit; the image forming apparatus being characterized in that the height adjusting unit is configured to adjust a height of the attachment table to a transfer execution height in accordance with a height of the object attached to the attachment table at the transfer position, and hold thus obtained height information, then, the height adjusting unit is configured to lower the attachment table to a height where the object does not make contact with an intermediate transfer belt of the transport unit, after the adjustment of the height of the attachment table by the height adjusting unit, the transport unit is configured to move the attachment table to a preparation position, when the attachment table moves to the preparation position, the height adjusting unit is configured to adjust the height of the attachment table to the transfer execution height on the basis of the held height information. an attachment table to which an object is attachable; a transfer unit configured to transfer an image onto the object; a transport unit configured to transport the attachment table along a transport path that has a transport start position on one side relative to the transfer unit and has a transport end position on a same side as the transport start position relative to the transfer unit, the transport path extending beyond the transfer unit and the attachment table being transported so as to turn back at a position beyond the transfer unit; and a height adjusting unit configured to adjust a height of the attachment table, wherein: the transport unit is configured to transport the attachment table to which the object has been attached to a transfer position of the transfer unit; the image forming apparatus being characterized in that the height adjusting unit is configured to adjust a height of the attachment table to a transfer execution height in accordance with a height of the object attached to the attachment table at the transfer position, and hold thus obtained height information, then, the height adjusting unit is configured to lower the attachment table to a height where the object does not make contact with an intermediate transfer belt of the transport unit, after the adjustment of the height of the attachment table by the height adjusting unit, the transport unit is configured to move the attachment table to a preparation position, when the attachment table moves to the preparation position, the height adjusting unit is configured to adjust the height of the attachment table to the transfer execution height on the basis of the held height information. the transport unit is configured to transport the attachment table to which the object has been attached to a transfer position of the transfer unit; the image forming apparatus being characterized in that the height adjusting unit is configured to adjust a height of the attachment table to a transfer execution height in accordance with a height of the object attached to the attachment table at the transfer position, and hold thus obtained height information, then, the height adjusting unit is configured to lower the attachment table to a height where the object does not make contact with an intermediate transfer belt of the transport unit, after the adjustment of the height of the attachment table by the height adjusting unit, the transport unit is configured to move the attachment table to a preparation position, when the attachment table moves to the preparation position, the height adjusting unit is configured to adjust the height of the attachment table to the transfer execution height on the basis of the held height information.