The experiments were held about the composition of the rice straws 4 species 37samples produced in the Northern Chosen where the climatic condition of temperature, sunshine are bad, and 8 species 21 samples in the Southern Chosen where these condition are better. The influence of the bad climate upon the composition are : Both total nitrogen and protein nitrogen are high, but non-protein nitrogen has not any distinct tendency. Cellulose and lignin are always low. Crude ash and silica are much contained. The tendency can be recognized that there are much phosphor and kali but a little calcium in ash. It seems to be the cause of the frail quality of the rice straws that there are much inorganic matter as silica, phosphor and kail ; on the other hand, there are few organic matter as cellulose, lignin which make the frame of the plants, but much protein, Nawa (straw-rope) and Kamasu (straw-bag) produced in Northern Chosen is too frail to be used for.