The catalytic conversion of CH4 to ethane was studied on metal nano cluster TiO2. We have used TiO2 nano cluster (Fig. ) as our substrate for adsorption of CH4 molecule. The HOMO-LUMO gap TiO2 cluster was calculated to be 2.63eV≈470 nm in wave length. The TiO2 nano cluster The oxygen removal from TiO2 nano cluster generates three unique sites for binding with CH4 on the TiO2. We studied their binding energy at the three different sites (Fig. ). It was found that CH4 prefer adsorption to Ti atom via a weak non-bonding interaction (Fig. ). The binding energy of TiO2 with CH4 without oxygen vacancy and positive charge is -1.84 kJ/mol. The creation of an oxygen atom vacancy in the TiO2 cluster increases the CH4 binding with Ti atom on the surface of cluster (Table ). The further addition of a positive charge increases the binding energy (Table ). From the CH4…Ti binding energies, it was found that the oxygen removed from position 3 (Fig ) was found to more stable. The next stronger binding was found for the CH4-TiO2 system where oxygen was removed from the site 1 and the least binding for site 2. From the above binding energies it was confirmed that the CH4 prefers binding of Ti atom with an oxygen vacancy at site 3 of TiO2 cluster (3).