Due to a high global warming potential,SF_6 has been listed as one of the emission limited gases.It has become an effective way to carry out harmless degradation of SF_6 waste gas to reduce SF_6 emission.To study the effects of different dilution gases for the degradation of SF_6 by the double dielectric barrier discharge (DBD) plasma,four kinds of gases (He,Ar,N2,air) were chosen and the concentration of SF_6 was 2% in this paper.The Q-U Lissajous figures of discharge were measured to calculate the discharge power.Under the conditions of the different input power with the same frequency,the discharge characteristics of different dilution gases were investigated.The concentration of SF_6 was detected after different degradation time to obtain the degradation rate.The experimental results showed that more uniform and stable DBD was produced with He or Ar as a dilution gas than with N2 or air.Besides,the degradation efficiency of He or Ar was better than that of N2 or air.Meanwhile it consumed less energy and time when SF_6 was completely degraded.In terms of the energy and degradation efficiency,monatomic gas should be selected to be a dilution gas for the degradation of SF_6.