An image capturing apparatus, includes: an image capturing element configured to capture an image of a subject; and a focusing control unit configured to perform a focusing control by a phase difference AF method using detection signals of first signal detection units and second signal detection units; a matching degree generation unit configured to generate a first matching degree which corresponds to a matching degree of two images captured by a first pair using the detection signals of the respective signal detection units of the first pair, and a second matching degree which corresponds to a matching degree of two images captured by a second pair using the detection signals of the respective signal detection units of the second pair; and a credibility determination unit configured to determine credibility of the focusing control by the phase difference AF method based on the first matching degree and the second matching degree.