Abstract: The physiological and biochemical changes during the senescence of tree peony flowers were studied with different Ca2+ contents The results showed that,with the increase of Ca2+ content, total blossom period could be prolonged by 1～2 days, nevertheless, high Ca2+ content declined the blossom rate Application of Ca2+,some physiological and biochemical indexes such as MDA content,O2- production rate and ethylene release rate diminished and the soluble protein content, SOD activity and photosynthesis increased Those changes obviously maintained the structure and integrity of membrane, and then alleviated the process of senescence of tree peony flowers