Abstract: To extend the vase life and improve the ornamental quality of cut tree peony（Paeonia suffruticosa）flowers，Box-Behnken center-united experiment was designed concerning three factors （waterborne acrylic resin，tea tree oil and plasticized coating time）on the basis of single-factor test. Then the response surface regression analysis was conducted to obtain the optimum ingredients of cut tree peony flowers coating process. The results showed that the optimum proportion for the ingredients were waterborne acrylic resin 82.95 g ? L-1，tea tree oil 0.65 mL ? L-1 and continuing coating 10.28 min. Under these conditions the cut tree peonies were stored at room temperature for 5 d，and after that the total color value（ΔE）was measured to be 2.15，and the color value of the control group was 6.64. It was found that this process could prolong the ornamental time，lower water loss rate，reduce the shrinkage rate of the floral diameter，improve the physical properties of the petals and suppress the occurrence of natural diseases to a large extent.

Key words: tree peony, cut flower, plasticized coating, waterborne acrylic resin, tea tree oil