The diploma thesis deals with impact of chemical composition polymers on formation of volatile products during thermal degradation. The aim of work is to analyze volatile products generating during thermal loading on selected kinds of natural and synthetic polymer materials. Natural polymers were represented by samples of two trees – Spruce norway and Oak summer. For the deputy of synthetic polymers were selected samples of expanded and graphite polystyrene. Product of natural polymers were collected until thermal loading of samples with temperatures 150 °C, 200 °C, 250 °C a 300 °C and products of synthetic polymers until temperatures 100 °C, 150 °C, 200 °C, 250 °C a 300 °C. Gaseous products were processed with method gas chromatography with mass spectrometry detection (CG-MS). During analysis were fixed large amount of compounds. Dominant were compounds classified as benzene derivatives (toluene, ethylbenzene) and terpenes (α-pinene, limonene). The most compounds were identified at samples of spruce and oak. Their increasing appearance with rising of thermal loading proves progressive degradation of main components of wood with rising temperature. Determination of volatile products during thermal degradation of polymers is important especially in term of safety, because these substances are flammable and some materials are producing toxic substances, which can endanger health and life of human. It’s necessary to regard this during proposing areas, which are used to evacuate people, their gathering and to interventions in case of fire.