Primary hepatic lymphoma is extremely rare,and only a few cases have been described on positron emission tomography(PET) or PET/computed tomography(PET/CT) imaging in the English literature.We report a case of a 55-year-old woman who presented with low-grade fever and weight loss of three months.On CT scanning,a mass was identified which appeared to be a hypoattenuating lesion,on ultrasonographic imaging,the mass was hypoechoic,therefore,liver abscess or hepatic metastasis from a gastrointestinal primary was initially suspected.Tumor markers such as alpha-fetoprotein,carcinoembryonic antigen and carbohydrate antigen 19-9 were within normal limits.PET/CT demonstrated a large abnormal ring-like hypermetabolic focus in the right liver lobe.The lesion was resected and the histo-pathological findings were consistent with lymphoma.The patient was discharged two weeks after surgery and did not receive any further treatment.After 25 mo follow-up,she is in good health.18F-fluorodeoxyglucose PET/CT is useful in confirming the diagnosis of primary hepatic lymphoma by demonstrating no other foci with high uptake in other parts of the body. Primary hepatic lymphoma is extremely rare, and only a few cases have been described on positron emission tomography (PET) or PET / computed tomography (PET / CT) imaging in the English literature.We report a case of a 55-year-old woman who presented with low-grade fever and weight loss of three months. On CT scanning, a mass was identified which appeared to be a hypoattenuating lesion, on ultrasonographic imaging, the mass was hypoechoic, therefore, liver abscess or hepatic metastasis from a gastrointestinal primary was previously suspected. Tumor markers such as alpha-fetoprotein, carcinoembryonic antigen and carbohydrate antigen 19-9 were within normal limits. PET / CT demonstrated a large abnormal ring-like hypermetabolic focus in the right liver lobe. lesion was resected and the histo -pathological findings were consistent with lymphoma.The patient was discharged two weeks after surgery and did not receive any further treatment. After 25 mo follow-up, she is in good health. 18F-fluorodeoxyglucose PET / CT is useful in confirming the diagnosis of primary hepatic lymphoma by demonstrating no other foci with high uptake in other parts of the body.