Focal nodular hyperplasia (FNH)of the liver is a lesion characterized by a well-circumscribed region of hyperplastic liver tissue with stellate fibrosis.The pathogenesis of FNH is unkown but various authors consider that this lesion may be a response to a preexisting vascular abnormality. The aim of this study is to review the clinical and diagnostic aspects of 12 documented cases of FNH and to assess the evolution and managment of this condition in cases reviewed. The diagnosis of FNH of the liver was based on imaging studies (ultrasonography,computed tomography and magnetic resonanse imaging)in all cases and additionally on histopathological examination in 3/12 patients.Physical examination and biochemical tests were performed as a part of the diagnostic evaluation and then during the observation period. The follow-up was from 1 to 7 years. In 4/12 cases the course was asymptomatic.The most common clinical manifestations were abdominal pain (7/12 patients),elevation of gamma-glutamyl transpeptidase (7/12)and typical imaging findings of FNH with computed tomography and magnetic resonanse imaging (well-circumscribed highly vascular mass situated in the liver with a stellate central star). Three of 12 patients were subjected to surgical resection of the tumors because of size of the tumor and diagnostic doubts.In all 3 cases pathological examination of the surgical resection confirmed the diagnosis of FNH. We emphasize the importance of a magnetic resonanse imaging scan in the diagnosis of hepatic FNH. Despite the same diagnosis different clinical manifestations and imaging studies may lead to different management.