Abstract: The vibrational energy transfer in SF_6-UF_6 system has been investigated using a pulsed TEA CO_2 laser for excitation of SF_6 and SF_6~* is employed as a sensitizer to excite UF_6 molecule. The transient changes in UV absorption of the vibration- ally excited UF_6 molecules in 220-320 nm region have been observed. For 2.0 Torr SF_6+2.0 Torr UF_6 system, three different kinds of vibrationally excited UF_6 have been found and their V-V intermolecular energy transfer times are 6.8, 9.0 and 26 μs, the V-T energy relaxation times are 42, 8.0 and 1 ms respectively. The vibrational energy transfer mechanism of SF_6-UF_6 system has been discussed.