Objective: To evaluate the efficacy of treatment in ovine babesiosis. Design : Experimental study. Animals: Thirty six sheep about 1-2 year -old. Procedure: Thirty six sheep , which were negative for any blood parasites, were selected. The animals were categorized into the splenectomized and unsplenectomized groups and each group into 3 subgroups: control, Diminazen and Imidocarb ones. Babesiosis was induced by intravenous injection of 5.2 x10o infected erythrocytes per animal.When body temperature and parasitemia raise, Diminazen (3.5 mg / kbw) and Imidocarb (1.2 mg / kbw) were administrated to each animal in the corresponding groups. Animals were kept up to day 9 post infection. After clinical manifestations, blood samples were daily collected from each animal and hematological parameters determined. Statistical analysis:t-student test. Discussion and Results : The results indicated that Diminazen is more effective than Imidocarb. Furthermore, clinical signs and parasites were recurred in the treated sheep with Imidocarb .