In an imaging device according to one aspect of the invention, an amplitude demand Ac is specified according to a wobbling amplitude Ai required for detection of a hill-climbing direction based on an F value and a wobbling amplitude Ag required for detection of the hill-climbing direction based on an AGC gain. An allowable amplitude Am set for preventing a potential image shake caused by a magnification change with a position shift of a compensator lens in wobbling is specified corresponding to a zoom position and an object distance. When Ac>Am, the control procedure restricts the wobbling amplitude to Am and increases a sampling number of AF evaluation values to be detected at respective positions in wobbling, in order to ensure the sufficient detection performance of the hill-climbing direction. When Ac□Am on the other hand, the control procedure sets Ac to the wobbling amplitude. This arrangement of the imaging device efficiently ensures the sufficient detection performance of the hill-climbing direction for autofocusing control, while effectively preventing deterioration of the quality of a captured image due to the magnification change in the wobbling motion.