Sixty-four regions are established on an image sensed picture from a video camera, where evaluating value r.sub.ij, b.sub.ij, and y.sub.ij is obtained by averaging color difference signals R-Y and B-Y and luminance signal Y obtained from an image sensing signal for over 1 field period for each region. When the apparatus determines that the difference in the evaluating values between two adjacent regions does not exceed a predetermined value, that is, when that continuing regions have the same color, the weighing amount of the color evaluating values of a corresponding region is adjusted to limit its effect upon the gain control signals used to adjust the gain of the color signal amplifiers. As a result, the effect of objects of the same color towards white balance adjustment is reduced.