Abstract: Taking ‘Tangier 99’ tomato seedlings as experimental materials, the tomato was studied by four treatments, normal temperature+0 mmol·L^-1 sucrose（CK）,normal temperature+50 mmol·L^-1 sucrose（T1）,low temperature+75 mmol·L^-1 sucrose（T2） and low temperature+0 mmol·L^-1 sucrose（T3）,in order to provide reference for the rational application of exogenous sucrose in tomato facility cultivation.The results showed that, compared with CK,exogenous spraying sucrose could significantly promote the growth of tomato plant height, the change of stem diameter, the underground dry weight/fresh weight, and significantly improved the strong seedling index of tomato.Effectively promoted tomato production, significantly increased the number of tomato fruits and improved tomato quality and flavor.Improved the activity of antioxidant enzymes and reduced the content of hydrogen peroxide（H₂O₂）.Exogenous sucrose could improved tomato seedling growth, promoted tomato growth and development, increased tomato yield and optimize quality under cold stress.By regulating antioxidant enzyme activity, the self-regulation balance of plant cells could be ensured, oxidative damage can be reduced, and the tolerance of tomato to cold stress could be improved, which further proved that exogenous sucrose spraying played an important role in relieving cold damage of tomato.