IFN-gamma, a Th1 cytokine was quantitatively estimated using EASIA in the sera of patients with different stages of schistosomiasis mansoni autoimmune diseases and schistosomal arthropathy. Level of IFN-gamma was significantly elevated in all the test groups compared to the control group. The highest level of IFN-gamma observed was in RA and SLE, with insignificant statistical difference (P > 0.05) between them. Cases with early S. mansoni infection showed significant higher level (P < 0.05) of IFN-gamma compared to hepatosplenic schistosomiasis with and without ascites. A significant statistical difference (P < 0.05) concerning IFN-gamma level was observed when comparing RA and SLE to different stages of S. mansoni infection and schistosomal arthropathy. This might lead to a conclusion that IFN-gamma estimation in sera of patients having joint complaint could be a good marker for differentiation between autoimmune collagen induced arthritis and schistosomiasis induced arthropathy.