Objective To evaluate the value of superb micro-vascular imaging in evaluating the therapeutic efficacy of liver cancer treated with radiofrequency ablation(RFA). Methods Thirty-five patients with hepatic cancer(40 lesions) were detected with Color Doppler Flow Imaging(CDFI), SMI and contrast-enhanced CT(CECT) before and 1 month, 3 month, 6 month after RFA treatment. The blood flow in the lesions were evaluated. Adler semi-quantitative assessment was used for grading, and CECT was used as the gold standard to analyze the correlation between the SMI grading in lesions and ablation effect before and after PFA. Results Before PRFA treatment, SMI showed that 5 lesions(12.5%) were in the first degree, 20 lesions (50.0%) were in the second degree and 15 lesions(37.5) were in the third degree. During the arterial phase, CECT showed that 3 lesions(7.5%) were mild enhancement, 19 lesions(47.5%) were moderate enhancement and 18 lesions(45.0%) were apparente enhancement. The correlation analysis showed that there was close consistency between the SMI and CECT(Kappa＝0 .752，P＝0 .00). After PRFA treatment , there was no statistical difference between SMI and CECT in evaluating the therapeutic efficacy of RFA(P＞0.05). The complete ablation rate of the lesions in the third degree of SMI before RFA treatment was lower than those in the first and second degrees(P＜0.05). Conclusions SMI has a good consistency with CECT in evaluating the blood flow signal of liver cancer. The microvascular grading of SMI technology has preliminary implications for the therapeutic efficacy of RFA and has potential clinical reference values.