The analysis of pre-treated wood surfaces, which have been plasma modified is also very informative for wood quality. Our measuring instruments determine the wettability based on the contact angle. The optical shape analysis of drops which are dispensed onto the surface is a reliable method for carrying out this measurement. The aim of this study was to verify possibility of determining the contact angle values of the plasma activated wood and calculate the surface free energy and its components of wood from the obtained contact angle values using Zisman, Equation of state (EOS), Fowkes and Wu theory and calculation method. Based on the contact angle data, the surface energy was obtained from the polar-dispersive(non-polar) approach. This study has been created as part of a large investigation on plasma- chemically activated wood surface and flame retardant treated wood.