This diploma thesis has been focused on analysis of surface properties of beech wood that modified by a CO2 laser. There were monitored colour and morphological changes to beech wood surface subject to laser treatment under different irradiation doses, wetting of surfaces treated un this way, with standard liquids, and there were also determined free surface energy values for these surfaces. The beech wood surface irradiation was accomplished according two different procedures and with using two different CO2 lasers. The results of the first experimenter showed that increasing the irradiation dose over a range of 0-75 J ∙ cm² induced significant overall colour (E =45). This discolouration was caused by a significant decrease in brightness (from 73 to 30%), also by decreased the colour coordinates a* a b*. Significant morphological changes were not detected but at the highest irradiation dose, with the entire surface layer carbonised and the surface roughness increased With increasing the irradiation dose, the surface free energy values of beech wood decreased. The wood surface modified in this way, however, complied the requirements for surface treatment with coatings and for gluing.In the second experiment, the intensity of beech wood surface irradiation was controlled by adjusting the performance power and the raster grid size of the laser beam. The experimental results showed that higher performance power and finer raster grid modified significantly wood colour (darkening), with significantly increased roughness and waviness parameters of the wood surface. Despite these changes, the studied beech wood displayed high surface free energy also in this case, satisfying the requirements for surface treatment and gluing. A negative aspect is undue surface roughness with possible negative impacts on the glued joint´s quality.