The effect of sunlight on the amount of the invertable carbohydrat in Pisum sativum etc. was studied under three different light intensities as in the previous investigations. Dried tissue of each plant was hydrolyzed with 2 per cent HCl for 3 hours at 100°C.. Total amount of suger was determined by the Amos-Peter's methode. The results of the experiment were as follows: 1. During the initial period of growth, the total amount of suger was in inverse proportion to the intensity of illumination, 2. But after the initial period the total amount of sugar in the plants was proportional to the light intensity. 3. Sugar substance appears to be synthetized to non-invertable substances like cellulose by light. 4. The results of the experiments on Allium ledebourianum, Phleum pratense L. and Cucumis sativus were almost the same to that of Pisum sativum.