Introduction <p>The association between serum zinc (SZn) concentration and fracture risk in postmenopausal women was investigated.</p> Materials and Methods <p>Women (<i>n</i> = 851) with a history of natural, premature, or surgical menopause who had completed data, including SZn concentrations at baseline (2009–2011), were included and followed through March 2018 for the incidence of any fracture requiring inpatient care. Potential non-linear and dose–response associations between SZn and fracture risk were assessed using a restricted cubic spline model (RCS) in Cox regression with the likelihood ratio test (LRT). Multivariable Cox proportional hazard models were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of fractures across the categories of SZn [&lt; 86, 86–135 (as reference), and ≥ 135 μg/dL].</p> Results <p>During a median follow-up period of 8.8 years (interquartile range: 8.1–9.2 years), 4.3% of postmenopausal women (with a mean age of 61.4 ± 8.6 years) experienced a new incident fracture. The mean of baseline SZn concentration was 113 ± 39.3 μg/dL. The LRT indicated no significant non-linear association (<i>P</i> = 0.176) and no evidence of a dose–response relationship (<i>P</i> = 0.448) between SZn and fracture risk. Using the categorical approach, the multivariable-adjusted Cox model showed that postmenopausal women with SZn concentrations below 86 μg/dL had a significantly increased risk of fracture compared to those within the reference range (86–135 μg/dL), with an HR of 2.29 (95% CI = 1.02–5.16, <i>P</i> = 0.044). SZn concentrations exceeding the reference range (≥ 135 μg/dL) were not associated with risk of fractures (HR = 1.47, 95% CI = 0.61–3.58).</p> Conclusions <p>Suboptimal SZn levels, indicative of inadequate zinc status, may contribute to an increased risk of bone fractures in postmenopausal women.</p>