Objective To exploring the expression of microRNA-93-5p(miRNA-93-5p)and neuregulin protein 1(NRG1)in thyroid cancer tissues and their relationship with clinicopathological characteristics and survival prognosis.Methods Frozen tissue specimens of 136 patients with thyroid diseases who underwent surgical treatment in the hospital from January 2018 to May 2020 were selected,including 84 cases of thyroid cancer(thyroid cancer group),52 cases of benign thyroid diseases(benign thyroid disease group),and another 40 cases of normal thyroid tissues(control group).The relative expression levels of miRNA-93-5p and the positive expression rate of NRG1 in the tissues of the thyroid cancer group,the benign thyroid disease group and the control group were compared,and the relationship between the expression of miRNA-93-5p and NRG1 in patients with thyroid cancer and the clinicopathological characteristics was analyzed.Multivariate Logistic regression was used to analyze the influencing factors of miRNA-93-5p and NRG1 expression.Kaplan-Meier survival curve was used to analyze the relationship between the expression of miRNA-93-5p and NRG1 and survival prognosis in patients with thyroid cancer.Results There were statistically significant differences in the relative expression levels of miRNA-93-5p and the positive expression rate of NRG1 among the thyroid cancer group,the benign thyroid disease group and the control group(P＜0.05).The relative expression level of miRNA-93-5p in thyroid cancer tissues was negatively correlated with the positive expression rate of NRG1(r=-0.216,P=0.013).The proportion of tumor maximum diameter＞1 cm,the rate of moderate and low differentiation,the rate of capsular invasion,the rate of lymphatic metastasis,and the proportion of TNM stage Ⅲ+Ⅳ in the miRNA-93-5p high-expression group were higher than those in the miRNA-93-5p low-ex-pression group(P＜0.05),and the above indicators in the NRG1 high-expression group were all lower than those in the NRG1 low-expression group(P＜0.05).Multivariate Logistic regression analysis revealed that the maximum diameter of the tumor,degree of differentiation,capsular invasion,lymphatic metastasis and TNM stage were all influencing factors for the expression of miRNA-93-5p and NRG1.The 3-year cumulative survival rate of the miRNA-93-5p high-expression group was lower than that of the miRNA-93-5p low-expres-sion group(P＜0.05),and the 3-year cumulative survival rate of the NRG1 high-expression group was higher than that of the NRG1 low-expression group(P＜0.05).Conclusion In thyroid cancer tissues,miRNA-93-5p is highly expressed and NRG1 is lowly expressed.Both can be used as biomarkers for evaluating the survival prognosis of patients.