This paper deals with high stable polysulfide preparation.The results show that temperature,time,stirred speed and Na_2S concentration have an obvious effect on polysulfide yield and its effectivity.Efficient liquor can be prepared by addition of sulfur to a higher concentration white liquor,which is stirred at 100 r/min and kept at 80 ℃ for 30 min.The decomposition rate of polysulfide sulfur can be reduced by additive A.