Background <p>Research investigating the impact of the non-essential metal (NEM) mixture on non-alcoholic fatty liver disease (NAFLD) among the elderly is presently insufficient. This study investigated the relationships between individual NEMs, their mixtures, and NAFLD in elderly individuals residing in Chinese communities.</p> Methods <p>The analysis included 2741 participants drawn from the baseline survey of a longitudinal study. Urinary concentrations of aluminum (Al), gallium (Ga), arsenic (As), cesium (Cs), barium (Ba), thallium (Tl), uranium (U), and cadmium (Cd) were quantified using inductively coupled plasma mass spectrometry (ICP-MS). NAFLD diagnosis was determined using abdominal ultrasound imaging. Logistic regression and restricted cubic spline (RCS) models were utilized to evaluate the relationships between individual NEMs and NAFLD. Additionally, Bayesian kernel machine regression (BKMR) and quantile-based computation regression (QGC) models were employed to assess the impact of the NEM mixture on NAFLD.</p> Results <p>After adjusting for covariates, Tl was significantly associated with an increased likelihood of NAFLD (<i>OR</i> 1.26, 95% <i>CI</i> 1.10–1.44). Both RCS and BKMR models confirmed a linear relationship between urine Tl and the risk of NAFLD. Additionally, both BKMR and QGC models highlighted a significant connection between the NEMs mixture and NAFLD, identifying Tl as the primary driver. Significant interactions were observed between Tl and Ba, as well as between Tl and hypertension (<i>P</i>_{<i>interaction</i>} = 0.055) and Tl and central obesity (<i>P</i>_{<i>interaction</i>} = 0.008), collectively demonstrating synergistic impacts on NAFLD risk.</p> Conclusions <p>The NEM mixture is associated with a higher risk of NAFLD in Chinese old adults, with Tl as the primary contributor. Additional investigation is required to validate these findings and shed light on underlying biological pathways through which co-exposure to NEMs contribute to NAFLD.</p>