A study has been done to find the effect of purification of crude antigens, extracted from adult Fasciola gigantica and Fasciola hepatica worms on the sensitivity of some serological techniques in diagnosis of fascioliasis. Using C.I.E.P. test, the partially purified antigens of both Fasciola species were less sensitive than their corresponding crude ones. Using I.H.A., the difference between results of crude and partially purified antigens for the two species were statistically insignificant, both (P greater than 0.05). So in applying this test, there is no need for the partially purification of antigen. On using E.L.I.S.A. the partially purified antigens showed higher sensitivities for detection of fascioliasis than their corresponding crude ones. Partially purified F. gigantica and F. hepatica antigens gave nearly the same results whether using C.I.E.P., I.H.A. or E.L.I.S.A. However, E.L.I.S.A. was the most sensitive technique followed by I.H.A. then C.I.E.P.