This study included preparation of hydatid antigen from hydatid fluid collected from Echinococcus granulosus cysts found in camels and in humans. Six types of hydatid antigens were applied for immunodiagnosis of hydatid disease in a batch of sera collected from 93 cases including 32 cases previously diagnosed as hydatidosis, 41 cases of other parasitic infections and 20 normal negative controls. Characterization of the affinity purified hydatid fluid antigen was performed using SDS-PAGE and EITB. ELISA test was performed to detect different anti-hydatid antibodies (IgG, IgM and IgA) using different preparations of the camel and human antigens. Also sandwich ELISA was performed to detect hydatid circulating antigen using anti-rabbit Con-A purified camel and human sera. Based on the results of the present study, we concluded that the specific protein bands are 55, 80 and 110 kDa. During detection of anti-hydatid antibodies, the highest sensitivity was recorded when using crude antigens, while the highest specificity was recorded when using host (human) free hydatid antigen. During detection of circulating hydatid antigen, the sensitivity was found low. This may be due to immune complex formation as well as the chronic nature of the disease, while the specificity is higher with better results when using antigens from human source. Based on the results of the present study, we recommend using host (human) free hydatid antigen (high diagnostic efficacy) in detection of anti-hydatid IgG (chronic nature of the disease) to diagnose hydatidosis.