Abstract: Self-made alkaline phosphatase (AKP) was prepared from pig intestine and then coupled with goat antihuman-IgG by one step glutaraldhyde method, the maximum titer of the conjugate being 1:6 400.Using Schistosoma japonicum soluble egg antigen as coating antigen, the positive rate of AKP conjugate was 100% in 54 proven patients with schistosomiasis japonica. The positive rates for sera from normal adults, pupils, patients of schistosomiasis, para gonimiasis, clonorchiasis, fascialopsiasis and filariasis were 2.1% (6/280), 0% (0/212), 96.5% (222/230), 2.80(1/35), 5.1%(5/98), 00(0/5) and 6.3%(5/79), respectively. The results showed that the AKP conjugate used in ELISA for schistosomiasis presented higher sensitivity and relative specificity.