A belt driving controller includes a driving roller connected to a driving axis, a plurality of driven rollers, an endless belt provided to surround the driving roller and the driven rollers in a tensioned state, a motor connected to the driving axis via a reduction mechanism; a first detector provided near the driving axis and configured to detect a rotation angle of the driving axis, a second detector configured to detect a displacement of the endless belt, and a control unit configured to control driving of the endless belt.