The objective of this work was to use the geotechnology study as a planning tool in determining the costs of forest extraction. The research was carried out in areas of the Forest Company that operates in the southern region of Bahia, Brazil. The work was developed in two stages, the first corresponding to the determination of production costs of the forwarder and the second in the machine’s productivity, taking as parameter the project area and the distance of extraction. The proposed methodology allowed to estimate with precision the distance of extraction, being this variable of great influence in the costs of forest extraction. The evaluated project presented 256.30 hectares of eucalyptus plantation, divided into 10 plots, with an extraction mean distance of 200 meters. According to the study, it would require the value of US$ 102,575.33 for the extraction of the wood from the project evaluated.