In this study, the noncontact and simultaneous 2D temperature and concentration measurement method has been developed to elucidate the reaction characteristics and improve the relevant simulation code. The technique is based on a CT method using absorption spectra of molecules such as H2O, NH3 and CH4. The CT Tunable diode laser absorption spectroscopy (TDLAS) method using 16-path laser beams was applied to measure 2D temperature, NH3 and CH4 distributions in engine exhausts and oscillating flames. Simultaneous and time resolved 2D temperature, NH3 and CH4 distributions were successfully reconstructed using a set of 16-path absorption spectra. Since CT TDLAS has a potential of kHz response time, this method enables real-time 2D temperature and species concentration measurements in various industrial processes including engine applications.