Abstract: 【Objective】 To study the effects of selenium on the growth and photosynthetic characteristics of muskmelon (Cucumismelo L.) as an essential nutrient element for higher plant growth in the hope of providing a theoretical basis for the establishment of control technology to improve the yield and quality of melon. 【Method】 Under the condition of autumn cultivation in Turpan, the melon cultivar Xizhoumi 17 was sprayed with amino acid selenium for 5 times from the initial flowering stage.The main stem length, stem diameter, internode length, leaf area, net photosynthetic rate (P_n) and transpiration rate of leaves at different nodes were measured at different growth stages taken clear water as the control. 【Result】 Exogenous amino acid selenium fertilizer treatment significantly promoted the growth and development of melon, and improved the photosynthetic capacity of leaves.In the fruiting stage (T₃), netting stage (T₅) and mature stage (T₆), the net photosynthetic rate of leaves at fruiting stage (T₃), netting stage (T₅) and maturity stage (T₆) was 26.29%, 53.51% and 301.56% higher than those of the control treatment, respectively, and the difference was significant (P>0.05) and delayed the speed of the functional leaves entering the senescence stage. 【Conclusion】 The growth rate of stem diameter and internode length of main vine was the fastest from the first flowering stage (T₁) to the full flowering stage (T₂), and the fastest growth rate of main vine length and leaf area was from full flowering stage (T₂) to fruiting stage (T₃).The stem diameter and leaf area of main vine of A₂₀ and A₂₅ treatments were significantly higher than those of the control treatment from T₅ to T₆; the net light of leaves at different nodes in A₂₀ and A₂₅ treatments at three growth stages was significantly higher than that of control treatment.The photosynthetic rate was significantly higher than that of the control treatment, which significantly improved the photosynthetic capacity of leaves and prolonged the functional period of leaves at different nodes.Therefore, spraying 2,000-2,500 times amino acid selenium fertilizer is an ideal regulation measure to delay the senescence of melon functional leaves.