This study investigated the relationship between essential plasma metals (Co, Cr, Cu, Mn, Mo, Se, Zn) and telomere length in 2,194 Chinese adults aged ≥ 30 years. Metal concentrations were measured using ICP-MS, and leukocyte relative telomere length (rTL) was assessed by qPCR. In the elderly, Cr and Mn were significantly positively correlated with rTL, while Mo, Zn, and Cu showed negative correlations. In the 30-59 age group, the overall metal mixture was significantly negatively associated with rTL (estimate = -0.069, P = 0.003), with Zn as the dominant contributor. In the elderly, the metal mixture was positively associated with rTL (estimate = 0.040, P = 0.031), with Cr and Mn as main contributors. The findings highlight the importance of maintaining adequate Cr and Mn levels in older adults, and the potential adverse impact of Cu, Mo, and Zn on telomere length.