The thermal decomposition reaction of ethyl bromide was studied in the temperature range of 724.5-755.1 K. Pressure dependence of the reaction was observed in its fall-off region. A theoretical evaluation of the rate constants was calculated adopting RRKM formulation in the region and was compared with the experimental observations. The validity of theory was also reevaluated by using the observed results. The observed activation energy in this study and Arrhenius A-factor were 51.7 kcal/mole and $10^{12.5}$, respectively. The small A-factor in the study was discussed in terms of the formation of a tight activated compex and the molecular elimination as a prevalent reaction mode.