The fourth harmonic of a pulsed Nd∶YAG laser is used to pump Raman cells filled with D₂ and D₂/He. The influence of the systemic parameters,such as the pump energy,pressure of pure D₂,and addition of He into D₂/He,on the energy conversion efficiencies and energy stability of stimulated Raman scattering radiations,have been experimentally studied.It is proved that the energy conversion efficiency and energy stability of S₁ is influenced by the intensity and energy stability of pump laser and the pressure of gas medium in Raman cell. On the premise of not lowering the energy stability of the first Stokes radiation(S₁,289.04 nm),it is propitious to increase the energy conversion efficiency of S₁ to add proper ratio of He into Raman cell filled with D₂. The maximum energy conversion efficiency of S₁reaches 22.1% in D₂/He. By experimental analysis,the conditions for optimizing the energy conversion efficiency and energy stability of S₁ have been gotten.