Thermomechanical curves for natural beech wood, beech lignomer and pure polystyrene in the absolute dry state at compression loads of 0.05, 0.5 MPa have been plotted. A decrease of the vitrification temperature along with increasing compression load has been found. The vitrification temperature for natural wood lies within the limits of 192-241°C. Polystyrene undergoes devitrification at the temperature of 82-112°C. The lignomer vitrification temperature is only slightly lower as compared with natural wood. At the loads of 0.05 and 0.5 MPa the vitrification temperature id practically wqual for both natural wood and lignomer, whereas at the load of 5.0 MPa the lignomer vitrification temperature is by about 10°C lower as compared with natural wood.