Abstract: The cotyledon leaves of peony（Paeonia suffruticosa） cultivars Fengdan was used as the initial explants,the effects of different species,concentration and compatibility of plant hormones on the regeneration process of peony cotyledon leaves were studied,including callus induction,adventitious bud differentiation and adventitious root induction. The results showed that the use of 0.1% mercury immersion for 7 minutes,then 10% sodium hypochlorite solution soak for 5 minutes is the best disinfection method,aseptic rate and germination rate of embryo were 82.96% and 56.03%. The optimum naphthylacetic acid （NAA） concentration in callus occurrence was 3.0 mg/L and the callus induction rate was 85.03%. The optimum medium for the adventitious buds occurrence was WPM+1.0 mg/L 6-benzylamino purine（6-BA）+0.3 mg/L NAA along with the frequency of differentiation was 77.35% and average number of adventitious buds was 3.05. The suitable medium for adventitious bud elongation was WPM+0.3 mg/L 6-BA+2.0 mg/L gibberellin（GA₃）. The elongation efficiency was about 81.12%,and the average shoot length was 1.93 cm. The optimum rooting medium was 1/2MS+2.0 mg/L NAA+1.5 mg/L indole butyric acid（IBA）+1.0 mg/L AgNO₃,the rooting rate reached 54.31%.

Key words: peony（Paeonia suffruticosa）, cotyledon leaves, regeneration system