Numerous anthropometric equations have been developed to estimate body density (BD) for various populations. The purpose of this study was to examine the use of 20 existing equations for estimating BD in 12 competitive male bodybuilders (24.0 +/- 3.0 yrs.: X +/- SD). Actual BD was determined by underwater weighing corrected for residual Lung volume. Anthropometric measures taken in duplicate included skinfolds (SF), circumferences, and diameters. Measurements were taken one to two days prior to actual competition. The bodybuilders were characterized by a body weight of 81.24 +/- 13.96 kg, BD of 1.0812 +/- 0.0099 g[middle dot]ml-1, and relative fat of 8.48 +/- 3.90 percent. Comparisons of the 20 equations revealed 12 equations with similar predicted BD when compared to actual BD. Pearson r values for these 12 equations ranged from .62 to .81. With the additional considerations of number of measures, intertester variability, and preference for quadratic equations, the equation of Lohman, BD = 1.0982 - 0.000815 (triSF + scapSF + abdSF) + 0.0000084 (triSF + scapSF + addSF)2, was found to be particularly appropriate for the estimation of BD in extremely muscular and lean body builders. The use of these equations may also be appropriate for estimating BD in male athletes with similar physical characteristics, such as wrestlers, gymnasts, and certain football players, as well as others.