Beta-mannan, also known as beta-galactomannan, is found in a number of feed ingredients for poultry. Of these, soybean meal (SBM) is by far the most commonly used, being the primary source of protein in poultry feeds in most countries. Although beta-mannan has clearly been shown to be deleterious to poultry and animal performance, a survey of its concentration in SBM has yet to be reported. Thirty-six samples of SBM, identified as either dehulled or nondehulled, were obtained from commercial sources in a number of countries and assayed for beta-mannan content. Results confirmed that all samples of SBM assayed contained at least 1.0% beta-mannan and that concentrations are higher in nondehulled (1.61 +/- 0.20%) than in dehulled samples (1.26 +/- 0.14%).