An image sensing apparatus includes an image sensing element to form an object image which enters via a photographing optical system, a distance measuring unit to measure distances to at least first and second points within a photographing frame using an optical path different from the optical system. A determination unit determines a relationship between a distance measuring result and a drive amount of the optical system, on the basis of the distance measuring result upon measuring a distance to the first point by the distance measuring unit and a change in contrast of the object image formed at a position corresponding to the first point on the image sensing element when a focal point position of the optical system has changed. A control unit controls the focal point position of the optical system, on the basis of a distance measuring result at the second point and the relationship.