In order to investigate effects of adhered molecules and internal motion of oxygen molecules on reaction probability and energy transfer to metallic surface, we carried out a classical molecular dynamics simulation by using LEPS potential energy surface between an oxygen molecule and Ag surface. Reaction probability of oxygen molecules much depends on internal molecular motion, such as vibrational temperature and rotational temperature of oxygen molecules as well as coverage ratio of adhered molecules on the surface. Reaction probability averaged over incident angle of oxygen molecules has linear relation to the coverage ratio of adhered molecules on the surface. As a result, energy transfer to Ag surface averaged over incident angle of oxygen molecules has linear relation to the coverage ratio only when the coverage ratio is small.