Seasonal changes of carbohydrate and nitrogen contents of the lower parts of rice culms whose leaf blades were cut of at six different stages (stem elongation, head initiation, 10 days before earing, earing, 10 days after earing, and milk stages) were studied. Contents of total nitrogen and protein nitrogen were scarcely affected by the leaf blade excisions; but soluble nitrogen somewhat increased by the cuttings treated at 10 days before earing and earing stages. On the contrary contents of carbohydrate decreased by the cuttings treated at 10 days before earing and earing. Similar tendencies were seen on the C/N ratio. Contents of carbohydrate and C/N ratio of all treated and non ?treated rice plants decreased rapidly after milk stages.