Shake amount detection device and imaging device

A shake amount detection device comprises: an acceleration sensor (8); a vibration period detection unit (7331); a speed change estimation unit (7332); a speed calculation unit (7333); and a shake amount calculation unit (7334). The acceleration sensor (8) detects the acceleration of the housing. The vibration period detection unit (7331) detects a period during which vibration greater than a prescribed threshold acts on the housing. The speed change estimation unit (7332) estimates a change in speed of the housing during the vibration period on the basis of the acceleration detected by the acceleration sensor (8). The speed calculation unit (7333) calculates the speed of the housing on the basis of the acceleration, and corrects the speed on the basis of the speed change estimated by the speed change estimation unit (7332). The shake amount calculation unit (7334) calculates an image shake correction amount for the vibration applied to the housing on the basis of the speed corrected by the speed calculation unit (7333).