ABSTRACT Objective Our aim is to investigate the correlation between CEUS quantitative parameters and MVD in thyroid papillary carcinoma(PTC),and also to provide a non-invasive preoperative detection method about microvascular evaluation for PTC.Methods Retrospective analysis was performed on 61 patients with thyroid nodules (61 nodules in total) who underwent thyroid CEUS examination in the ultrasound department of our hospital, Quantitative parameters of CEUS enhanced mode time-intensity curve (TIC) of thyroid nodules were analyzed and compared with surgical pathological results. CD31 immunohistochemical staining was performed on the surgically resected thyroid nodules to count MVD. Pearson method was used to analyze the correlation between CEUS quantitative parameters and MVD.Results CEUS indicated that 55 PTC nodules showed heterogeneous and low enhancement pattern. The accuracy of CEUS in diagnosing PTC was 90.1%. The TIC、PI and AUC 55 PTCs were (14.47±6.42)dB and (603.1±222.80)dB?s,respectively,which were lower than (21.06±5.65)dB and (1025.43±260.37) dB?s in the surrounding normal thyroid tissues,and differences were statistically significant(P<0.05).The mean MVD of CD31 immunohistochemical staining PTC was (64.99±17.51) twigs/HP,which was lower than (91.71±7.54) twigs/HP in surrounding normal thyroid tissue,and the differences were statistically significant(P<0.05).A significantly positive correlation was observed between PI 、 AUC and MVD in PTC(r=0.811、0.734,P<0.001). Conclusion CEUS and quantitative analysis can improve the diagnostic accuracy of thyroid nodules.This study provides useful research basis and experimental basis for the effective evaluation of PTC for CEUS before preoperative.