1. An image pick-up apparatus, comprising: an image pick-up unit; a dividing unit which divides a central area of an image pick-up range of the image pick-up unit into a predetermined number of regions; a judging unit which judges, based on a variance of colors of an image picked up by the image pick-up unit corresponding respectively to the regions divided by the dividing unit, whether or not an object image for adjusting white balance exists in a vicinity of a center of the image pick-up range; and a first setting unit which adjusts gain values of color components only in each of the predetermined number of divided regions, and sets white balance of the image pick-up range according to the adjusted gain values, when the judging unit judges that the object image exists.