OBJECTIVE: To observe the influence of Qingrehuatan decoction(QRHT) on serum metabolic profile in young essential hypertension(YEH) patients with abundant phlegm-heat syndrome and provide a basis for treatment with the decoction.METHODS: Twelve male YEH patients were randomly selected and serum samples were collected for examination before and after 4 weeks of thetreatment with QRHT. Twelve healthy males were randomly selected and their serum samples were collected as a control. All serum samples were detected using metabolomic technology with1 H nuclear magnetic resonance. Differences in metabolites were studied by principal component analysis and partial least squares-discriminate analysis,which produced scores and loadings plots.RESULTS: After 4 weeks of treatment, serum substances could be distinguished between the YEH patients with abundant phlegm-heat syndrome and the control patients. The specific serum endogenous metabolites tended to improve after the treatment. QRHT can appropriately increase the levels of glucose, lactic acid, citric acid, high-density lipoprotein, phosphatidylcholine, glycerophosphate choline, hydroxybutyrate, alanine, and glutamate.QRHT could also decrease the levels of low-density lipoprotein/very low-density lipoprotein, lipids,N-acetyl glycoprotein, and O-acetyl glycoprotein.CONCLUSION: QRHT can effectively ameliorate metabolic disorders in YEH Patients with abundant phlegm- heat syndrome.1H NMR-based metabolomic technology can provide an objective basis for the treatment of YEH patients with abundant phlegm-heat syndrome using QRHT.