Features of enhanced color flow images of small hepatocellular carcinoma (HCC) were studied to elucidate their usefulness in evaluating tumor hemodynamics. Enhanced color Doppler using the contrast agent "SH/TA508" was performed on 16 patients, 13 with HCC, 1 with regenerative nodule, and 2 with hemangiomas, in whom the size of the tumor were smaller than 30 mm. Enhanced color flow appearance was compared with angiographic findings. Significant improvement in the detection of color flow signals was obtained in small HCC using SH/TA508, from 33% in pre-contrast to 92% in post-contrast (p < 0.005). Three patterns of enhanced color flow images, which were related to the angiographic findings, were observed. Enhanced color flow imaging promises to be a useful method for evaluating tumor vascularity noninvasively, and to contribute to the elucidation of the hemodynamics in liver tumor.