This study examines the relationship between dietary protein intake and bone mineral density (BMD) using data from the 2011-2018 National Health and Nutrition Examination Survey (NHANES), addressing existing controversies in current evidence. This cross-sectional study included 16,775 participants. Dietary protein intake, the exposure variable, was collected with the use of two 24-h dietary recall methods and usual intake was assessed by the National Cancer Institute (NCI) method. While whole-body BMD, the outcome variable, was measured with dual-energy X-ray absorptiometry. Covariates included demographic, socioeconomic, and health factors. Weighted multivariable regression and generalized additive models were used for the association between dietary protein intake and BMD. After adjusting for covariates, a positive association was found between protein intake and BMD. Each additional gram of protein consumed was significantly associated with a BMD increase of 0.0003 g/cm