The left ventricular hypertrophy index (LVMI) is a vital metric for assessing LVH, a major complication of hypertension. The triglyceride-glucose (TyG) index combined with obesity indicators is an emerging marker of insulin resistance (IR), positively associated with cardiovascular disease.In this cross-sectional analysis of 4,551 Chinese adults with hypertension, we evaluated associations between TyG-derived indices (TyG-WC, TyG-BMI, and TyG-WHtR) and LVMI using multivariable linear regression models adjusted for potential confounders, including age, sex, blood pressure, urea, among others. We performed subgroup analyses, incorporating interaction tests, to evaluate the stability of results across demographic and clinical strata.Significant positive associations were found between quartiles of TyG-BMI, TyG-WC, TyG-WHtR, and elevated LVMI. TyG-BMI showed the strongest dose-response relationship, with progressively increasing ? coefficients (95% CI) across ascending quartiles (Q2: 3.163 [2.141–4.184], Q3: 4.754 [3.720–5.788], Q4: 8.055 [7.002–9.109]) compared to Q1. Subgroup analyses showed consistent trends (all interaction P-values >0.05), suggesting homogeneous associations across demographic and clinical subgroups. Our findings reveal robust associations between TyG-obesity indices (particularly TyG-BMI) and LVMI in hypertensive individuals with hypertension. The consistency of these associations across clinical subgroups highlights the potential of TyG-obesity indices as composite biomarkers for monitoring cardiac remodeling in hypertension management.