The reactions of Cl,F and O atoms with methane recently have been the focus of experimental1-3 and theoretical4-8 investigations to study mode selective enhancement and energy requirement on reactivity.We performed quantum dynamics,time-dependent wavepacket method to study the energy efficiency in surmounting the reaction energy barrier and vibrational enhancement on reactivity of the forward and reverse reactions of O atom with CH4.The purpose of these studies is to investigate energy requirements on reaction reactivity on more than 4 atom polyatomic reaction systems and to see if the Polanyi role9 can be extended to these reactions.