Abstract: The thermal decomposition of n-heptane is an important process in petroleum industry. The theoretical investigations show that the main products are C₂H₄, H₂, CH₄, and C₃H₆, which agree well with the experimental results. The products populations depend strongly on the temperature. The quantity of ethylene increases quickly as the temperature goes up. The conversion of n-heptane and the mole fraction of primary products from reactive molecular dynamic and chemical kinetic modeling are compared with each other. We also investigated the pre-exponential factor and activation energy for thermal decomposition of n-heptane by kinetic analysis from the reactive force field simulations, which were extracted to be 1.78×10¹⁴ s^-1 and 47.32 kcal/mol respectively.