A blur correcting device includes a shake detecting unit configured to detect a shake and output a detection signal indicating a result of the detection; a drive unit configured to displace a relative positional relationship between a lens unit and an image pickup element relative to an optical axis such that a position of an optical image formed on an image pickup surface of the image pickup element is displaced on the image pickup surface; and a control unit configured to increase a displacement range when the amount of shake indicated by the detection signal is larger than a predetermined level, displace the relative positional relationship between the lens unit and the image pickup element within the increased displacement range in accordance with the detection signal, and thereby correct a blur of the optical image on the image pickup surface caused by the shake detected by the shake detecting unit.