Toxoplasma gondii, an obligatory intracellular protozoan parasite, is one of the causative agents of ovine abortion, as reported in many countries. Different techniques are being used to detect this pathogen in infected ovine fetuses. One of the most sensitive and specific diagnostic techniques is Nested-PCR amplification of the B1 target gene of the organism. In total, 200 brain samples of aborted ovine fetuses and maternal sera submitted from different parts of Khorasan Razavi province, Iran were investigated to track the role of Toxoplasma gondii in ovine abortion by a slightly modified Nested-PCR and IFAT assays, respectively. Among all samples, 27 (13·5%) were PCR-positive and 31 (15·5%) were IFAT-positive and the Toxoplasma-induced abortion prevalence calculated was 8·8% to18·2% with 95% confidence interval. Results show that high levels of congenital transmission may occur in 27/31(87%) of pregnancies with an excellent logical agreement (ĸ=0·9) between 2 different tests. According to the results of this study, the Nested-PCR employed in this investigation could be recommended as an applied routine test for the routine examination and confirmation of Toxoplasma gondii-induced ovine abortion.