The chemical components of Huanglian Decoction were identified by ultra-performance liquid chromatography-quadrupole-time-of-flight-tandem mass spectrometry(UPLC-Q-TOF-MS/MS) technology. The gradient elution was conducted in Agilent ZORBAX Extend-C_(18) column(2.1 mm×100 mm, 1.8 μm) with the mobile phase of 0.1% formic acid aqueous solution(A)-acetonitrile(B) at a flow rate of 0.3 mL·min~(-1) and the column temperature of 35 ℃. The MS adopted the positive and negative ion mode of electrospray ionization(ESI), and the MS data were collected under the scanning range of m/z 100-1 500. Through high-resolution MS data analysis, combined with literature comparison and confirmation of reference substances, this paper identified 134 chemical components in Huanglian Decoction, including 12 alkaloids, 23 flavonoids, 22 terpenes and saponins, 12 phenols, 7 coumarins, 12 amino acids, 23 organic acids, and 23 other compounds, and the medicinal sources of the compounds were ascribed. Based on the previous studies, 7 components were selected as the index components. Combined with the network pharmacology research and analysis me-thods, the protein and protein interaction(PPI) network information of the intersection targets was obtained through the STRING 11.0 database, and 20 core targets of efficacy were screened out. In this study, UPLC-Q-TOF-MS/MS technology was successfully used to comprehensively analyze and identify the chemical components of Huanglian Decoction, and the core targets of its efficacy were discussed in combination with network pharmacology, which laid the foundation for clarifying the material basis and quality control of Huanglian Decoction.