In order to investigate the diagnostic value in differential diagnosis of primary liver tumors, color Doppler sonography was used preoperatively in 30 patients. Without difference, tumor hypervascularization was found in patients with hepatocellular carcinoma (2 of 4), cholangiocellular carcinoma (4 of 4), hemangioma (3 of 8), focal nodular hyperplasia (8 of 8), adenoma (3 of 4), and neuroendocrine tumor (n = 1). No vascular signal could be detected in 1 case of adenomatous hyperplasia and 2 cases of hepatocellular carcinoma, one after previous chemoembolization. Hemangioma appeared hypo- or even avascular in 5 of 8 patients. Therefore, according to our experience, the yield of color Doppler sonography is rather low for differential diagnosis and prediction of the tumor dignity. With regard to the surgical procedure, valuable information about tumor extension can be obtained particularly in central lesions close to hilar structures or liver vein confluence. Further indications result from follow-up of tumor vascularization after chemoembolization and chemotherapy.