The aim of the study was to investigate the effect of exogenous salicylic acid (SA) pretreatment on the growth, chlorophyll contents, osmotic adjustment substance contents and antioxidant system of melon seedlings under chilling stress (12 ℃/ 6 ℃) and 7 days’ recovery condition (28 ℃/ 22 ℃). Cultivar ‘Hongyou’ seedlings were treated with different concentrations of SA (including 0.1, 0.5, 1.0 and 2.0 mmol·L^-1) in climate chambers. The results showed that： (1) chilling stress significantly inhibited the growth of melon seedlings, different concentrations of exogenous SA pretreatment could alleviate the damage induced by chilling stress, and 1.0 mmol·L^-1 SA has the most notable effect. 1.0 mmol·L^-1 SA significantly increased plant height, stem thickness, and fresh weight of melon seedlings.(2) Suitable exogenous SA pretreatment also increased soluble sugar, soluble protein and proline contents, promoted osmotic adjustment.(3)In addition, exogenous SA pretreatment could strengthen the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR) and dehydroascorbate reductase (DHAR), increase the contents of ascorbic acid (AsA) and glutathione (GSH), improve the ratios of ASA/DHA and GSH/GSSG, so the electrolyte leakage, malondialdehyde (MDA) content and reactive oxygen species (ROS) greatly reduced. Overall, appropriate concentration of exogenous SA pretreatment could promote the growth and chilling tolerance of melon seedlings, through increasing osmotic adjustment substance contents, enhancing antioxidant enzyme activities and activating AsAGSH cycle.