The adult worms of cestodes, Moniezia expansa and Diphyllobothrium mansoni employed in this experiment. The worms were divided into three portions, i.e. immature , mature and gravid proglottids, and each proglottids were incubated in a certain incubation period, and the glucose uptake rate, total CO₂ production rate, tissue concentration and their radioactivities were employed as previous reports(Rim et al., 1965). The glucose uptake rate by M. expansa was a mean value of 6.46±1.23 micromole per hour per gram of wet wt. and the rate by D. mansoni was a mean value of 18.8±0.8 µM per hour per gram of wet wt. The higher rates were observed in the mature proglottid of M. expansa and in the immature proglottid of D. mansoni. The total CO₂ production rates by the worms averaged 14.0±2.37 µM per hour per gram in M. expansa and 17.51±1.54 µM per hour per gram of wet wt. The relative specific activities of respiratory CO₂(R.S.A CO₂) averaged 22.2±5.15 percent in M. expansa and 54.2±2.2 per cent in D. mansoni. In the both worms, the higher values were obtained in the mature proglottids. Therefore, the average value of 8.84±2.66 per cent of glucose utilized by M. expansa and 8.23±0.50 percent of glucose utilized by D. mansoni from the medium glucose was oxidized into respiratory CO₂. The tissue concentrations of glycogen were a mean of 2.21±0.46 percent per gram of wet wt. in M. expansa and 7.56±1.24 percent per gram of wet wt. in D. mansoni. The higher concentration of glycogen was observed in the gravid proglottids of M. expansa, however the gravid proglottids of D. mansoni showed lower concentration of glycogen than the other proglottids. The turnover rate of glycogen pool yielded with a mean of 0.04±0.01 miligram per hour per gram of wet wt. of M. expansa, whereas a mean of 1.66± 0.46 miligram per hour per gram wet wt. of D. mansoni. Therefore, a mean value of 2.58±0.93 per cent(R.G.D gly) of glucose utilized by M. expansa and 53.6±1.4 percent by D. mansoni was incorproated into the glycogen . These data account for that at least 11.42 per cent of the utilized glucose by M. expansa and 61.83 per cent of the utilized glucose by D. mansoni participated in furnishing the oxidation into respiratory CO₂ and the synthetic process into glycogen.