Jinqi Jiangtang (JQJT) is a Chinese herbal formula modified from "Qianjin Huanglian pill", which has been recorded in Qian Jin Fang for treating "Xiaoke Zheng. Due to its therapeutic efficacy, JIT has been used for treating type 2 diabetes mellitus (T2DM in China for decades. It is approved as the first herbal formula for treating T2DM, recorded in Chinese Pharmacopoeia since 2010. JQJT consists of three herbs, including Coptidis Rhizoma, Astragali Radix, Lonicerae Japonicae Flos, each of which contains various kinds of therapeutic compounds. It is well believed that exactly these compounds lead to restoration of homeostasis via modulation of multiple targets in an additive, synergistic or antagonistic manner. However, berberine hydrochloride alone is the main quality marker for the quality control of JQJT in Chinese Pharmacopoeia. It is our belief that more efforts should be made towards a more comprehensive understanding of its underlying therapeutic mechanisms and pharmacodynamic material basis. Here, we sought to improve the quality control standardization of JQJT on the basis of its therapeutic efficacy and material basis, for maximizing the safety, stability, and effectiveness. Therefore, quality control methods for herbal medicines in terms of the identification of marker compounds were summarized in chapter 1. Based on the review in chapter 1, three experimental studies were carried out to decipher the molecular mechanisms and pharmacodynamic material basis of JOT on T2DM. In Study I of chapter 2, the pharmacological mechanism of JQIT against T2DM was clarified via network pharmacology analysis. Our results indicated that JQJT may exert therapeutic effects in T2DM by regulating insulin signaling and inflammatory response in a multi-components, multi-targets and multi-pathways manner. An online comprehensive two-dimensional liquid chromatography coupled to mass spectrometry was proposed to characterize the metabolome of JQJT in Study II of chapter 3, which identified 77 chemical ingredients in 60 min. In Study III of chapter 4, pharmacodynamic material basis of JOT were screened out by integrating plant metabolomics with chemometrics. As a result, 8 compounds have been identified as potential active components from JOT. These compounds could be considered as quality markers (Q-markers) for JQJT, which may contribute to the improved quality standard of JQJT. In conclusion, this work provides experimental evidence of JOT for the prevention and treatment of T2DM.