Combustion synthesis reaction due to the release of high energy and short processing time, is an effective and economic method to produce Ti-Al intermetallic compounds. It is worth mentioning that due to the very high rate of this process, direct experimental observations in determining the reaction mechanism are very difficult since there is a need for high precision and high resolution tools. For this reason, the molecular dynamics simulation method (MD) had been employed as a suitable replacement for the study of the atomic behavior of the system and explosive combustion synthesis reaction mechanism in the present work. In this way investigates the effect of stoichiometry Ti/Al ratio on thermal explosion and adiabatic temperature by the use of molecular dynamics code (LAMMPS) and the EAM potential. After the simulation, to compare the results with experimental results, some specimens of Al and Ti powders were prepared with stoichiometric ratio similar simulation conditions and then TE process were performed on specimens. In continuation, X-ray diffraction (XRD) analysis and photo techniques during synthesis were used for phase identification and determination the reaction time. The results suggested that the products formed during the TE, the reaction completion time and also the final adiabatic temperature were influenced by the Ti/Al stoichiometry ratio. In fact, the reaction mechanism has been in such a manner that the phases with lower Al contents were initially formed and then as the reaction progressed, the percentage of Al content increased in the formed compound. Accordingly, the first phase formed at the interface of the atoms was TiAl 3 . Additionally, the composition of the final product was equivalent to the initial stoichiometry ratio. In general, results were shown that the rate of the formation of the product and the reaction progress depend on two factors of the diffusion coefficient of atoms and the concentration difference. The final adiabatic temperature for the above-mentioned compounds was equal to 1765, 1810, 1890, 1880 and 1525 K with an increase in Ti/Al ratio. In laboratory study also indicated that the rate of reaction decreased by increasing the Ti/Al ratio and the formed phases in specimens were moved from the compounds with higher Al percentage toward the compounds with lower Al percentage. Therfore the results of the simulation and experimental methods confirm each other. In other words, the results wree shown that the formation of the product layers and their combination is from the compounds with higher Al percentage toward the compounds with lower Al percentage and diffusion is the most important controller factor in reaction. Keywords: Intermetallic compounds, Titanium aluminides, Explosion combustion synthesis prosses, Molecular dynamics simulation