The Brazil nut plant (Bertholletia excelsa Bonpl.) is native from Amazonia region. The nuts are extensively used as food and in cosmetic industries. During its processing, one of the most important parameters to be determined is its water content, which is critical to drying and storage steps. Thus, the objective on this study was to verify the accuracy of the method of oven at 105 °C to 24 h on water content measurement for Brazil nuts, in comparison to water content levels determined by Karl Fisher titration. It was verified that applying oven at 105 °C to 24 h to determine water content of Brazil nuts is not adequate, once the results were higher than those obtained from Karl Fisher titration. The samples submitted to oven showed high peroxide value, indicating its oxidation and consequent formation of volatile secondary compounds, which could be the reason to overestimation of water content determined.