S. mansoni adult worm crude antigen, snails antigens ( foot and visceral hump of B. alexandrina and B. truncates) and specific hyperimmune mice sera versus each antigen were prepared and used in diagnosis of S. mansoni infection by ELISA technique and western blot analysis. The results revealed the presence ofhigh similarity between S. mansoni crude antigen and those of B. alexandrina (foot and visceral hump) antigens in detecting of S. mansoni antibodies by 100% positivity. B. alexandrina foot antigen appeared more sensitive (80%) than visceral hump antigen (33.3%).Concerning the EITB specificity, bands at 74, 43, 38/39, 31/32, 13 KDa of S. mansoni fractionated adult worm antigen,74 KDa and 43 KDa in fractionated B. alexandrina foot antigen and 20 KDa in B. alexandrina visceral hump antigen reacted specifically versus anti S. mansoni antibody.