In this paper, the daily solar radiation incident at the top of Saturn's atmosphere and taking into account both the oblateness of the planet and the shadow of the ring system is calculated. It is found that the decrease of the daily insolation in winter is important near the solstices up to mid-latitudes and in the neighborhood of the equinoxes for equatorial and low latitudes. The combined effect of Saturn's rings and its flattening on the mean winter and annual daily insolations is also studied. The numerical results show that the mean wintertime insolation falls gradually in the (0-20 °) latitude region to a peak value of about 50%. Beyond 20° the loss of insolation decreases and from approximately 45 ‡ up to polar region latitudes the decrease reaches a practically constant level of 35%. The mean annual daily insolation is maximally reduced by about 20° at localities of 20°.