Abstract: Objective To investigate the correlation between serum transforming growth factor β₁（TGF-β₁） and carotid-femoral pulse wave velocity（cfPWV） in children with primary hypertension. Methods This was a cross-sectional study in which 82 children, 68 males（82.9%） and 14 females（17.1%）, hospitalized with a diagnosis of essential hypertension and untreated from January 2021 to August 2022 were selected, and 42 normotensive children were selected as the control group. The clinical data were analyzed. cfPWV measured by SphygmoCor cardiovascular function detector was assessed as the parameter of early arterial stiffness. Concentration of serum TGF-β₁ was detected by enzyme linked immunosorbent assay test（ELISA）. Spearman correlation coefficient was used to analyze the correlation between serum TGF-β₁ and cfPWV. Multivariable logistic regression was used to analyze the independent risk factors of early arterial stiffness. The receiver operating characteristic（ROC） curve was used to explore the value of variables in the diagnosis of early arterial stiffness. Results The case group had a TGF-β₁ level of 46.1（38.8, 49.0） ng/L, significantly higher than the 41.3（30.3, 47.1）ng/L from the control group（Z=-2.322, P=0.020）. Among 82 children with primary hypertension, the concentration of serum TGF-β₁ in stage 2 hypertension was higher than that in stage 1 46.1（38.8, 49.7） vs 38.8（35.6, 46.1）ng/L, Z=-2.424, P=0.015. The body mass index（BMI） and serum TGF-β₁ level in 16 patients with early arterial stiffness group were higher than those in 66 patients with normal arterial elasticity group （31.4±5.1） vs（26.3±4.0）kg/m~2, 48.8（46.1, 55.1） vs 46.0（38.8, 48.1）ng/L. The difference was statistically significant（t=-4.382, P＜0.001; Z=-3.189, P=0.001）. Spearman correlation analysis showed that BMI, heart rate, diastolic blood pressure（DBP）, 24 h mean diastolic blood pressure（24hDBP）, 24 h mean pulsatile pressure（24hMAP） and TGF-β₁ were positively correlated with cfPWV（r_s=0.318, P=0.004; r_s=0.239, P=0.031; r_s=0.244, P=0.027; r_s=0.294, P=0.007; r_s=0.267, P=0.015; r_s=0.482, P＜0.001）. The multivariate logistic regression analysis showed that BMI（OR, 1.260; 95%CI 1.041-1.525） and TGF-β₁（OR, 1.149; 95%CI 1.013-1.305） were the risk factors for early arterial stiffness. ROC curve analysis showed that the area under the curve of combined BMI and TGF-β₁ for the diagnosis of increased early arterial stiffness was 0.887（95%CI 0.805 to 0.970, P＜0.001）, with a sensitivity and specificity of 81.3% and 80.3%, respectively. Conclusion Serum TGF-β₁ is positively correlated with cfPWV, and BMI and TGF-β₁ are independent risk factors for early increased arterial stiffness, and combined BMI and TGF-β₁ have diagnostic value for early increased arterial stiffness in children with essential hypertension.