In this work, we present the results obtained from the methanolysis of soybean oil using tin(IV)-based commercial compounds as catalysts. In order to characterize the behavior of such catalytic systems in the reaction medium, different reaction times, temperatures and catalyst amounts were used. The efficiency of the catalytic system in terms of yield (% of fatty acid methyl esters formed) varies in the following order: dibutyltin dilaurate > di-n-butyl-oxo-stannane > modified di-n-butyl-oxo-stannane > butylstannoic acid. Parameters as degree of solubility of the catalyst and rate stirring were also investigated. (c) 2006 Elsevier B.V. All rights reserved.