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The freezingthawing phenomenons of fruits and vegetables are inevitable during the refrigerated transport process. The quality of fruits and vegetables will also be changed. Grapes as test objects are used to test the quality change during the freezingthawing process. The cryomicroscope system (including CCD camera, BCS 196 cryostage, the liquid nitrogen tank, the crystage temperature control system) was used to test the grape sample during the freezingthawing process. The temperature range of cryomicroscope system is -196℃ to 125℃. The crystallization change of grape cells has been researched. The freezingthawing rate is 2,6,8,11,14,20,50, 90℃/min. Micrograph, volume, internal pressure and permeability coefficient of grape cells were analyzed during the freezingthawing process. The result shows that the formation process of crystallization in the intercellular space depends on the freezing rate. Grape cell freezing temperatures will decrease with increasing freezing rate and the general trend of change in volume of grape cells will decrease with the decreasing of temperature. However, grape cells volume will increase at -5~0℃ due to the volume changes of intracellular free water. Grape cells volumes were reduced by 54.5%, 26.3% respectively at 14℃/min and 50℃/min freezing rates. The larger the freezing rate is, the smaller the cell volume changes to be. During the freezing process, the permeability coefficient of grape cells will decrease with the decreasing temperature and freezing rate. Increasing thawing temperature can effectively reduce the damage of the grape cells during freezingthawing process. This research will optimize the temperature gradient of fruit and vegetable during cold storage.