Alleviating effect of exogenous ABA on low temperature stress was further elucidated on the basis of find-ing suitable ABA mass concentration in tomato seedlings, by foliar-spraying with different mass concentration ofABA, taking the seedlings of tomato‘Dongnong 11537’as test materials. The results showed that after treatmentwith 200 μL/L ABA, the contents of proline and soluble sugar and soluble protein were up-regulated as the time ex-tended and the activities of the antioxidant enzyme and chlorophyll content were also significantly higher than CK atthe same time. However, the content of MDA was significantly lower than CK. The tendency of CBF1、SLCZFP1、SLCMYB1、LENLP4 all showed increasing trend, but the expression level of SLCMYB1, LENLP4 in treatment with thesuitable ABA was higher than CK. The study found that the ABA pretreatment of tomato seedlings can promote theexpression of cold-related genes and to improve the cold resistance.