We report an uncommon presentation of liver cancer in a 33-year-old woman who presented with persistent right shoulder pain with a normal physical examination of her shoulder and normal X-rays. An abdominal ultrasound scan and a computed tomography scan subsequently revealed a large liver cancer in this patient who was subsequently found to be hepatitis B positive. Extrinsic causes of shoulder pain should be considered when shoulder movement is normal and does not alter the character of the pain. Subdiaphragmatic liver lesions should be considered in the differential diagnosis of right shoulder pain. In any geographical area with a high incidence of hepatitis B infection, hepatocellular carcinoma should be included in the differential diagnosis of shoulder pain if a clear local cause is not identified.