Aim To investigate the relationship between triglyceride-glucose (TyG) index and the risk of hypertension in middle-aged and older adults in China, and to provide scientific basis for the prevention and treatment of hypertension. Methods Data were obtained from the China health and retirement longitudinal study (CHARLS) in 2011. A multi-stage stratified sampling method was used to select participants. Restricted cubic spline regression model was used to analyze the dose-response relationship between TyG index and the risk of hypertension. Multivariate unconditional Logistic regression model was used to evaluate the association between TyG index and the risk of hypertension.Results A total of 9 987 subjects were included in the analysis, with an average age of (59.16±9.43) years, including 4 707 males (47.13%). The restricted cubic spline regression model showed that the risk of hypertension increased with the elevation of TyG index, and there was a linear association (overall association test P＜0.000 1, non-linear association test P＝0.201 9). The results of multivariate Logistic regression model showed that compared with Q1 (TyG index＜8.23), the OR(95%CI) of hypertension with Q2 (8.23≤TyG index＜8.59), Q3 (8.59≤TyG index＜9.04) and Q4 (TyG index≥9.04), were 1.09 (0.95～1.26), 1.53 (1.33～1.76) and 1.77 (1.52～2.06), respectively. Conclusions With the increase of TyG index, the risk of hypertension gradually increased. TyG index may be an independent risk factor of hypertension.