Via two-hphoton resonant excitation of sodium atom (3S→4D) in Na-Na2 mixture by the laser at 578.7 nm, more than forty stimulated emission lines in the UV 320-370 nm region were obtuinted. Passing labeling and analysing, it has been demonstrated that the UV stimulated emiSSion lines are come from in Na2, which was excited by the FWM wave in Na as the consequent pumping source of the assemble.