Abstract: To investigate the effects of different concentrations exogenous AsA by foliar spraying on premature senescence and fruit quality of Hainan winter and spring protected netted melon, the growth condition, antioxidant enzyme activity, fruit quality and mineral nutrients accumulation of netted melon were analyzed under 5 concentrations of foliar spraying AsA solution with 0（ck）, 1, 3, 5, 7 and 9 mmol/L. The results showed that the treatment with concentration of 5-9 mmol/L AsA could significantly improved the leaf width, leaf length, leaf color value compared with ck. 5 mmol/L treatment significantly improved the antioxidant enzyme activity of fruit node leaves, delayed the decrease of soluble protein content and slowed down the increase of malondialdehyde content compared with ck. At the 3 mmol/L concentration, the soluble solid, vitamin C and crude protein of melon fruit significantly increased, which were 9.93%, 34.22% and 45.33% higher than that of ck respectively, At the same time, the contents of potassium and phosphorus were significantly higher than those of the ck.