Background: Fasciola hepatica is a genus of the trematodes which mainly affects the liver of sheep and these livestock are accidentally infected by eating plants or drinking water contaminated with the metacercariae of this parasite. These parasites can cause considerable economic damage by destroying the liver and bile ducts. OBJECTIVES: The aim of this study was to evaluate the role of ultrasonographic diagnosis in chronic hepatic fasciolysis of sheep and to provide ultrasonography views of fasciolosis in sheep’s liver. METHODS: In this cross-sectional study, 256 sheep of the Makoei breed, including 130 male (50.8%) and 126 female (49.2%) with diagnosis of chronic fasciolosis confirmed by the appearance of fluke eggs in feces and using enzyme-linked immunosorbent assay (ELISA) were referred to the Department of Radiology and Ultrasonography, Doppler ultrasound was performed. Average age of sheep was 2.1 years (minimum age 7 months and maximum age 6 years). Data were analyzed by SPSS software (version 11.5) and the statistical test was chi-square test. P value less than 0.05 was considered significant. RESULTS: In the results, 55.6% of sheep had ascites in the abdominal cavity and in 5.7% and 11.3%, bile ducts and gallbladder were affected, respectively, and in 4.8% of sheep both the liver and the bile ducts were involved. In 22.6% of sheep, there was no abnormal finding in ultrasound. The most common site of injury was in the posterior part of the right lobe of liver. There was no significant difference between the place of involvement in the liver, age and sex of the patients. CONCLUSIONS: According to this study, ultrasonography can play an important role in the diagnosis and follow up of sheep’s chronic fasciolosis treatment.