Abstract: With a modified, simple method, JEU was extracted from the remaining residue after SEA extraction. The positive rate in 150 proved schistosomiasis japonica patients was 96% by ELISA using JEU, and the false positive rate in 129 normal persons was only 0.8%.To evluate the therapeutic effectiveness, 255 patients with negative stool hatching after treatment were repeatedly tested by ELISA using JEU for a period of one to five years. The negative conversion rate increased year by year. The negative rate was 93.4% in three years, and 100% in five years. The antibody titer decreased more significantly than the positive rate.when JEU was parallelly tested with ELISA and IHA using SEA and COP in a village where schistosomiasis had been controlled, there was no significant difference among ELISA and IHA but ELISA using JEU was much better than COP.The results suggest that JEU is a new type of antigen of practical use in the diagnosis and evaluation of therapeutic effectiveness.