Esterases are enzymes that present good potential in industrial application, and soybean seed can represent an alternative source for this enzyme. The extraction and esterase activity of Brazilian soybean seeds (Glycine max L.) were evaluated. Esterase activity was found in both the germinated and non-germinated seeds at 2.90 and 1.70 U/mg, respectively, with a concentration in the powdered extract (freeze dried) of 100 mg/mL. The enzyme showed a preference for the hydrolysis of short chain fatty acids (120.02 U/mL) and optimum pH for activity was pH 8.0 with optimum temperatures of 40 and $80^{circ}C$. The enzyme showed stability at $70^{circ}C$ showing 60% of residual activity and activity increased with the addition of the following salts: $NaNO_3$, $K_2SO_4$, and $Na_2SO_4$ in the reaction medium.