Gancao Xiexin Decoction (GCXXD) is a traditional Chinese decoction that is often used in treating gastric ulcers. However, the substance basis and mechanism of action remain unclear. In this study, in vivo and in vitro components of GCXXD were analyzed by ultra-high-performance liquid chromatography coupled with quadrupole-orbitrap mass spectrometry. The compound Discover platform was used to ultimately enable rapid identification of compounds. Acquire X intelligent data acquisition technology software was innovatively adopted. In the process of collecting drug-containing plasma, all components detected in blank plasma samples were excluded to eliminate the interference and influence of endogenous components in plasma, making the analysis results more accurate and reliable. At the same time, the possibility of selecting precursor parent ions with low concentration levels within the chromatographic peak can be increased, improving the coverage and integrality of the detection of components in vivo. Also, the targeted network pharmacology strategy combined with molecular docking was established to explore the mechanism of GCXXD in treating gastric ulcers. As a result, 113 components were identified, 41 of which could enter the bloodstream and exert therapeutic effects in vivo. The main effective components are glycyrrhizic acid, 6-gingerol, jatrorrhizine, wogonin, palmatine, and liquiritigenin, main targets in vivo were related to ALB, IL6, and VEGF, which play an important role in anti-inflammatory and promoting angiogenesis. In summary, this study adopted a comprehensive analysis strategy to reveal the pharmacodynamic material basis and mechanism of GCXXD against gastric ulcers, providing a scientific basis for its clinical application.