The content of polyphenol,total flavonoids and antioxidant activity of mints by different drying method were studied and the HPLC chromatographic analysis was applied.The results showed that the microwave drying to peppermint and air drying to Scotland spearmint were the best drying method to keep the content of polyphenol and total flavonoids.Chlorogenic acid,caffeic acid,p-coumaric acid and rosmarinic acid were detected in peppermint and scotland spearmint.In peppermint,chlorogenic acid,caffeic acid and p-coumaric acid had the highest content under air drying and rosmarinic acid had the highest content under microwave drying.For scotland spearmint,chlorogenic acid,caffeic acid and rosmarinic acid had the highest content under air drying process.p-coumaric acid had the highest content under hot air drying,but had no significant difference with the other two drying methods.The antioxidant activity of peppermint reached maximum under air drying process in DPPH,FRAP and TEAC assay.The antioxidant activity of Scotland spearmint reached maximum under air drying in DPPH and FRAP assay,TEAC antioxidant activity reached maximum under microwave drying.