Abstract: Cut flowers of Eustoma grandiforum cultivars702 were used to determine the physiological and biochemical changes taking place in the flowers kept in vase. The results showed that the fresh weight, soluble proteins, soluble sugar, respiration rate, as well as SOD and CAT activities in the flower petals increased in the early stage and decreased later on. On the other hand, the relative electric conductivity and POD activity increased while being held in a vase. Damage on the cell membrane resulted from the decreased protective enzymes activity and membrane lipid peroxidation might induce senescence on the cut-flowers.