The objective of this work was to estimate and to analyze the elasticity of substitution between Brazil, the USA and Argentina in the soybeans exports in the selected importers markets. This fact is important, considering that, it increases the integration of the world economies, placing in prominence of the adaptability to the world demand, as a fundamental factor for the exports expansion. Like this, given the economical relevance of the Brazilian exports of soybeans it was looked for, specifically, to verify the substitution possibility between the soybeans exports of Brazil, the USA and Argentina. After accomplishment of Dickey-Fuller expanded tests (ADF) for unit root, and Trace test and Max-eingevalue test for co-integration, the Error Correction Model (ECM) was adopted in the estimate of the elasticity of substitution. That model was shown well adjusted to the datas, allowing to identify the presence or absence of market rigidity, even so there is not perfect substitution in the soybeans exports. This way, investment in differentiation of the product, through rastreability and identity preservation can impulse the Brazilian exports.