Using a heated shock tube and an spectroscopic detector ICCD,transient emission spectra of triethylamine in the combustion reaction were measured in the range of ultraviolet to near infrared .Experiments were conducted at a pressure of 1.5 atm and a temperature of 1500 K. Results show that the main emission bands are attributed to NO, OH, NH, CN and CH radicals produced during the combustion process,and the small radicals NO, OH, NH, CN, and CH are the important reaction products in the combustion process of triethylamine,and the spectrum of CN radical is obviously stronger than that of CH radical;Determined the electron level transitions corresponding to the characteristic spectra of NO, OH, NH, CN, and CH radicals. Analyzed the production mechanism of small free radicals of NO, OH, NH, CN and CH from the perspective of chemical reaction with the theory of combustion kinetics.The results provide experimental basis for understanding the microscopic process of triethylamine combustion reaction and verifying the mechanism of triethylamine combustion reaction.