Monieziosis is one of the most important parasitic diseases of sheep;causing great economical losses in milk, meat, wool, death, infertility and costs of treatment. The aim of this study is to evaluate Indirect ELISA (iELISA) as a method of sero-diagnosis for Moniezia expansa infestation among sheep at Giza governorate. Two hundred eighty three sheep were examined for the infestation with M. expansa by feacal examination using concentration floatation techniques to detect M. expansa eggs and examination of intestines of slaughtered sheep to detect adult worms of M. expansa. The somatic antigen used to screen antibodies in the sera of the examined sheep was prepared from the adult worm. IELISA was applied on total of 92 sheep serum samples. It was found that prevalence of M. expansa among the examined sheep as 28.3% (80/283) by faecal examination. The sensitivity, specificity and accuracy of ELISA were statistically calculated as 100%, 41.6% and 92.4%, respectively. It was concluded that iELISA is highly sensitive, less specific and highly accurate for the
serodiagnosis of Ovine Monieziosis.