A large number of studies conducted in Russia and abroad have been devoted to the development of low NOx emission gas turbine engines for aircraft and power stations. However, the continual improvement of the environmental requirements of ICAO (International Civil Aviation Organization) forces new research to be carried out to meet the future goals of reduced emissions produced by gas turbine combustors (GTE), a better understanding of the process of formation of various pollutants is required. Both empirical and theoretical approaches will be studied in this present research work to provide the exhaust concentrations of NOx emissions. In recent years different methods are already developed for this problem, one of them is associated with a theoretical approach. It is well known that correct theoretical models are economical (help’s to avoid experimental work) and can be useful for deep examination of NOx emissions generated in the combustion chamber process. The main objective of this study is to predict NOx emissions in GTE based on the mathematical simulations and chemical kinetics approach. To validate the simulation results, dispersion type optical system was developed in the laboratory. This system includes UV LED source (λ=245-280nm), single-pass absorption cell with length (L=500 mm) and spectrometer DFS-452 (spectral dispersion up to Δλ = 0.2nm/mm) equipped photo detector MORS-1 with a detection range Δλ=50nm. It allowed us to measure concentrations of some matters which absorbed light in the UVC range.