Hepatic injury is rarely associated with undifferentiated connective tissue diseases (UCTD). We report, here, a case of a middle-aged woman with UCTD-related hepatic injury, including its case history, clinical manifestations, laboratory findings, treatment and its short-term effect. The patient was admitted to the hospital with symptoms of fatigue, anorexia, low-grade fever and skin rashes. She had a past history of left knee joint replacement. Laboratory tests showed elevated levels of serum transaminase, IgG and globulin, accelerated erythrocyte sedimentation rate, eosinophilia and a high titer of antinuclear antibodies (1:320). Imaging studies showed interstitial pneumonitis and hydropericardium. Liver biopsy showed the features which were consistent with those of connective tissue diseases-related polyangitis. After treatment with a low-dose of oral prednisone, both symptoms and laboratory findings were significantly improved. UCTD-related hepatic injury should be considered in the differential diagnosis of connective tissue diseases with abnormal liver function tests. Low-dose prednisone may effectively improve both symptoms and laboratory tests.