Using the $Methionine-2-C^{14}$, the metabolism of methionine to the experimental rats on rice diet was studied comparing with that to the rats on stock diet in this paper. The National Institute of Health strain of weaning albino rats were housed into the individual cages deviding into 2 groups, the rice diet (RD) group and the stock diet (SD) group, and fed on rice diet and stock diet respectively for 10 weeks. On the day of experiment, the rats were parenterally administered. the $methionine-2-C^{14}$ solution after fasting over night. And then the rats were sacrificed by ether anesthesia by time being of one, three, six, and twelve hours each and the organs, pituitary gland, pancreas, spleen, liver, and kidney, were taken out for the determinations of radioactivities. And also the excretion of radioactivities through urine were determined by time being. The radioactivities were determined by Autoscaler SC-51 using the planchets. The results of radioactivities of urine excretion were shown at table 3 and the results of radioactivities distibutions in the organs by time being after parenteral administration of $methionine-2-C^{14}$ were shown table 4 in the original paper. According to the results, the following are summarized; 1. The growth experiment result of rats on. rice diet and stock diet were same as shown by the previous workers indicating significant growth inhibition at the rice diet group. 2. Due to the result of radioactivity excretion through urine after administration of $methionine-2-C^{14}$, it might he considered that methionine in the rice diet seems to be limited. However, it seems to be not 주 mostly limited. 3. And due to the results of radioactivity distribution in the organs by time being, the radioactivity in the liver tissue showed appearently higher readings at this methionine study compared with the results at the lysine study shown by HAW and his co-worker. This might be interpreted, though it is not clear, that liver might require methionine as a deficient amino acid at the tissue because methionine is limited at the rice diet.