A misregistration correcting device includes an image forming unit, a sensor, a reading unit, and a determining unit. The image forming unit form a set of misregistration correcting patterns that includes a reference pattern. The sensors start detecting the set when a predetermined time has elapsed after start of image formation for the first set. The reading unit reads positional information of the set upon detection of the set. The determining unit determines timing to start detecting subsequent sets of misregistration correcting patterns based on positional information of the reference pattern in the first set.