Supercooling point and freezing point of seven cut flower organs (petals, anthers, ovary, sepals, petioles, leaves and stems) from three tree peony varieties ‘Yumiantaohua’, ‘Qingxiangbai ’ and ‘Fengdan’ under the room temperature storage (in 15-18 ℃ storage for 3 d, RTS), coldacclimation storage ［in (4±1) ℃ storage for 3 d, CAS］ and ice temperature storage ［first in (4±1) ℃ storage for 3 d, and then turned to (-4±1) ℃ storage for 3 d, ITS］ conditions were studied, and contents of bound water, soluble protein, soluble sugar and proline in petals and leaves of tree peony cut flowers were also examined, respectively. Having been stored at 4 ℃ for 3d, the results of CAS showed that compared with the RTS, CAS significantly reduced the supercooling points(SCP) and freezing points(FP) of most cut flower organs of these three tree peony, increased the contents of bound water, soluble protein, soluble sugar and proline in petals and leaves. And after ITS for 3 d, the contents of bound water and soluble protein are further increased in petals and leaves, respectively. Thus, the CAS treatment significantly improved the cold resistance of tree peony cut flowers and favored the ITS. These results provide the technical basis for the regulation and control of ITS(-3 to -4 ℃) and for long time storage (30 to 150 d) of tree peony cut flowers.