Abstract: 【Objective】 In order to study the effect of LED monochromatic light on the storage characteristics and sugar content of muskmelon during storage and to develop a new technology for postharvest preservation of muskmelon. 【Methods】 The melon variety Xizhoumi25 was used as material, the effects of low light intensity of red, blue and white light-emitting diode on storage characteristics and sugar content of postharvest muskmelon were studied at 7 ℃ cryostat. 【Results】 LED of white light had the best effect on reducing rot and delay the decrease of hardness, and red light had the best effect on keeping the color of melon peel;it was found that the degradation rate of sucrose, glucose and sucrose in muskmelon flesh was delayed in the middle and late stage of storage by LED light treatment, according to the analysis of fructose, fructose and glucose in flesh by High-performance liquid chromatography. White light had the best effect on the sugar content of muskmelon during storage. 【Conclusion】 The results showed that LED delayed the decline of soluble solids content, and weight loss rate, kept the color of melon peel, reduced rot and delayed the decrease of pulp hardness.LED continuous illumination treatment has a significant effect on the preservation and sugar quality maintenance of muskmelon during storage.