Coccidiosis is a parasitic disease caused by the Eimeria spp. that affects sheep and ruminants and leads to important economic losses. Studying of incidence of coccidiosis will help us to decrease the coccidiosis infection in the sheep flocks, and resulting in novel control programs. The Eimeria prevalence in sheep is taken in the Diwaniyah city from March 2017 to February 2018. 200 sheep were used in this study ( 95Lambs and 105 Adult) that tested clinically by taking fecal samples and examined by a routine microscopic examination and conventional PCR. Results revealed that 57.5% of sheep were infected by the Eimeria parasite. Adult female sheep were more infected 77.9% than adult male sheep 41.3%, but in Lambs the parasite was higher in males 62% than the male 44.4%, also the overall prevalence of Eimeria spp. according to age was higher in adult's 60.9% than that in Lambs 53.6%. In conclusion, gender significantly affected the prevalence and severity of the infection. Age, possibly, might be a significant factor adding to the notable losses in sheep in the Diwaniyah city in Iraq.