The diploma thesis deals with the thermal loading of selected polyurethane foams, removal of the generated volatile products and their subsequent analysis by gas chromatography with mass spectrometry method. Results of qualitative analysis based on comparison of retention times and mass spectra of substances were recorded in the tables. Quantitative determination of selected volatile substances was performed by an external standard method. Each experiment was recorded in the pictures (photograph) that documents material changes at an established temperature. Three types of upholstery polyurethane foams - N 30 38, R 40 36 and F 57 40 were examined. Thermal loading was set up to 150 ° C, 200 ° C and 250 ° C. The main products are mainly toluene, ethylbenzene, and cyanide-based substances. It has been found that at lower temperatures, as many substances as at higher were not determined, this is confirmation of the gradual release of these compounds based on the thermal load. As the most susceptible to temperature, the sample R40 36 appears on the basis of the determined volatile products. The most stable sample was the flame retardation treatment F 57 40.