The authors studied the reaction between H2 and F2, which is highly exothermic in nature, experimentally and computationally. The reaction was carried out in a tubular reactor. Flow rates of H2 and the N2-F2 mixture were varied and the authors report the results in terms of temperature, velocity, and concentration at different locations of the reactor. Numerical simulations were carried out and the temperature profiles predicted by these simulations are compared with the experimental ones. A good match is observed between the two. It has been seen that the reaction temperature is different from what is reported by Wilson et al. (1951), when fluorine is premixed with inert gas like nitrogen. It is also observed that the flame due to the reaction between hydrogen and fluorine is formed in front of the fluorine feed nozzle. The investigation results are useful for the process design of an H2-F2 reactor.