An image capturing apparatus includes: an image capturing element in which a plurality of pixels is formed and arranged in a two-dimensional array pattern and phase difference pixels are formed within an effective pixel region; a photographing lens; a phase difference amount detecting unit analyzing a captured image signal by the image capturing element and obtaining a phase difference amount from detection signals of two of the phase difference pixels that make a pair; and a control unit obtaining a defocus amount of a photographic subject image picked up by the image capturing element from the detected phase difference amount and performing a focusing control of the photographing lens. The control unit obtains a parameter value regarding a ratio of the defocus amount and the phase difference amount based on photographing lens information of the photographing lens and a light receiving sensitivity distribution indicating sensitivity for each incident angle of incident light for the two of the phase differenc
