An image capture apparatus includes: an image sensor having a plurality of pixels that photoelectrically convert an object image formed by an imaging optical system, each of the pixels having one microlens and a photoelectric conversion portion that has been divided into a plurality of portions; a focus detection unit configured to correct an image shift amount detected with a phase difference detection method using focus detection signal arrays of two images obtained by the photoelectric conversion portions divided into a plurality of portions; and a controller that calculates information corresponding to a movement amount of a lens of the imaging optical system based on the image shift amount detected and corrected by the focus detection unit, and controls movement of the lens of the imaging optical system.