Abstract: To research the effect and regulation mechanism of 1-MCP treatment on sugar metabolism of peach, the soluble sugars and the transcription level of sugar metabolism related genes of"Xiahui 6"peach that were stored at 20℃ with 85%~90% relative humidity were determined. The results showed that 1-MCP treatment could keep a higher firmness compared to control group significantly (p<0.05). Besides, the respiration of peach could decreased and the peak of respiration could be postponed by 1-MCP treatment. 1-MCP could inhibit the increase of the content of glucose and fructose and the decrease of the content of sucrose. Total 14 genes related sugar metabolism were isolated and the expression of PpSPS, PpSS and PpNI had a higher level compared with the expression of PpAI. 1-MCP treatment could significaty enhance the expression of PpSPS4 and inhibited the transcript level of PpNI3, PpNI4 and PpSS1 during the middle storage (p<0.05). Conclusion:1-MCP could regulate the sugar metabolism mainly through up-regulating the expression of PpSPS4 and down-regulating the expression of PpNI3, PpNI4, which could result in a higher level of sucrose content.