The inhibitory action of oxygen consumption and parasiticidal action of hexachlorophene or MTPA combined with or without sodium cholate in Clonorchis sinensis (C.S) have been observed. The results were obtained as follows. 1. In low concentration of MTPA or Hexachlorophene, they inhibited the oxygen consumption of C.S and in high concentration, inhibition of oxygen consumption and parasiticidal action was more remarkable. 2. The oxygen consumption was inhibited also in the concentration of 10^-2 and 2 X 10^-3g/ml of sodium cholate. 3. In the presence of sodium cholate, oxygen consumption of C.S was more remarkably inhibited by MTPA or Hexachlorophene than the absence of sodium cholate. 4. From those results, it may be considered that sodium cholate combined with MTPA or Hexachlorophene produced potentiation in its action.