To provide an automatic focus adjusting device by which high-speed and highly accurate focusing is always attained.

This automatic focus adjusting device is provided with first focus adjusting means 15-18 to perform focusing by performing range-finding calculation, based on the integral quantity of a subject image signal obtained by photodetecting sensors 204a and 204b and second focus adjusting means 12-17 to perform the focusing by calculating a focus evaluation value, based on the subject image signal obtained by an imaging device 12 provided on the optical axis of image pickup optical systems 10 and 11, and pre-focusing is performed by the first focusing means, and then, main focusing is performed by the second focusing means. After a focusing lens is driven to a position on this side of focusing, based on an estimated focal point obtained by performing the pre-focusing by the first focusing means, the main focusing is performed next by obtaining the focus evaluation value, while driving a focusing lens position by the second focusing means, so that high-speed and highly accurate automatic focusing is performed.