An image capturing apparatus performs a global electronic shutter operation in which a plurality of pixels are exposed during the same exposure period. In a first period, charge is accumulated by a photoelectric conversion unit. In a second period, accumulation units of a plurality of pixels accumulate charge. A ratio of saturation charge quantity of the photoelectric conversion unit to saturation charge quantity of the accumulation unit has a certain relationship with a ratio of a length of the first period to the sum of the length of the first period and the length of the second period.