Abstract: Adult Schistosoma japonicum were found to contain a spectrum of purine bases; nucleosides and nucleotides including ATP, ADP, AMP, uridine, hypoxanthine, inosine, adenosine, adenine and GTP. ATP was rapidly converted to hypoxanthine by S. japonicum hoinogenates.The adenosine phosphorylase activity of S. japonicum was 27.3μmole/min/worm pair. This enzyme was released into the culture medium when the worms were incubated in vitro for 24 hours. Pyquiton(8 × 10-4M) and formycin A (1.6×10-3M) inhibited this, enzyme 58% and 72%, respectively.The ATPase activity of the tegument of male and female S. japonicum was found to be 17.313.8 and 17.0±2.5μmole Pi/hr/mg protein. In the presence of 3mM Mg2+, this enzyme was not activated by Na+ (100mM) and K+ (20mM), nor inhibited by ouabain (5×10-4M), suggesting that Na+-K+-activated ATPase might be absent in the tegument. This enzyme was isolated and purified by PAGE and isoelectric focusing and its Michaelis constant before and after purification was estimated.