Background: Hyperuricemia has been linked to various health conditions. However, the relationship between uric acid (UA) levels and lung function remains debated.Methods: In a cross-sectional study of 6750 participants aged 20-69 from NHANES, we assessed UA levels and lung function (FVC and FEV1). We conducted regression analyses while adjusting for potential confounders.Results: After accounting for factors like age, sex, BMI, smoking, and more, we found a negative association between UA FVC and FEV1. Specifically, for every 0.1 mg/dL increase in UA, FEV1 decreased by 15.265 mL, and FVC decreased by 24.46 mL. No association was observed with FEV1/FVC. Subgroup analyses revealed similar negative correlations among various groups, particularly in non-Hispanic Black females under 60.Conclusion: Serum UA levels are inversely associated with FEV1 and FVC in the American population, with a notable impact on non-Hispanic Black females under 60.