Objective To compare the effect of dynamic three-dimensional contrast-enhanced ultrasound（D-3D-CEUS）and enhanced CT（CECT）in the diagnosis of hepatocellular carcinoma and the evaluation of therapeutic effect after microwave ablation.Methods Eighty patients with hepatocellular carcinoma underwent microwave ablation in our hospital were selected.All patients were examined by D-3D-CEUS and CECT.The diagnostic efficacy

the internal display of the tumor in arterial phase

the blood supply vessels of the tumor and the tumor boundary of hepatocellular carcinoma of the two methods were compared.All patients were followed up for one year

based on the final results of clinical follow-up as the gold standard

the treatment efficacy of microwave ablation for hepatocellular carcinoma were evaluated by D-3D-CEUS and CECT.Results All patients were diagnosed as hepatocellular carcinoma by D-3D-CEUS

including 55 cases with the diameter<3 cm

and 25 cases with the diameter≥3 cm

and 21 cases with internal necrosis.All patients were also diagnosed as hepatocellular carcinoma by CECT

including 53 cases with diameter<3 cm

27 cases with diameter≥3 cm

and 22 cases with internal necrosis.There were no statistically significant differences between the two methods in the diagnostic efficacy of diameter and internal necrosis in hepatocellular carcinoma.The clarity of D-3D-CEUS in the blood supply vessels of hepatocellular carcinoma was better than that of CECT

and the clarity of tumor boundary of CECT was better than that of D-3D-CEUS

which had showed a statistical difference（both P<0.05）.There was no statistical difference between the two methods in the internal display of tumors in arterial phase.After 1-year follow-up

11 of 80 patients were finally diagnosed as local residual

69 patients were completely ablated

the accuracy rate of D-3D-CEUS efficacy evaluation was 91.25%（73/80）

the accuracy rate of CECT efficacy evaluation was 90.00%（72/80）

there was no statistical difference.Conclusion D-3D-CEUS is superior to CECT in the clarity of blood supply vessels of hepatocellular carcinoma

and CECT is superior to D-3D-CEUS in the clarity of tumor boundary.Both of them have good effect on the efficacy evaluation of hepatocellular carcinoma after microwave ablation.