Metabolic profiling of the crude ethanolic extract of Gliricidia sepium (Jacq.) Kunth. ex. Walp. stem ethanolic extract (GSS) was conducted using ultra-high performance quadrupole time of flight mass spectrometry/mass spectrometry (UHPLC-QTOF-MS/MS) in negative mode, resulting in the identification of 23 compounds belonging to various classes such as flavonoids, fatty acids, triterpenoid saponins, and phenolic acids. Notably, eight flavonoids including kaempferol-3-O-robinoside-7-O-rhamnoside, isoquercitrin, kaempferol-3-O-rutinoside, apigenin-7-glucoside, kaempeferol-7-O-rhamnoside, luteolin, apigenin, and liquiritigenin, along with two phenolic acids (4-hydroxycinnamic acid and 2-hydroxyhydrocinnamic acid) and four triterpenoid saponins (soyasaponin I, soyasaponin II, soyasaponin III, and kaikasaponin III) were dereplicated. Additionally, nine fatty acid derivatives were identified, including azelaic acid and 2-isopropyl malic acid. Molecular networking analysis revealed the formation of clusters among compounds while others do not form clusters. Further analysis indicated that the GSS ethanolic extract exhibited a total phenolic content of 38.78 ± 1.609 µg of gallic acid equivalent/mg and a total flavonoid content of 5.62 ± 0.50 µg of rutin equivalent/mg. Biological evaluations showed that GSS ethanolic extract mitigated gastric tissue injury induced by pyloric ligation, with a notable reduction in oxidative stress marker reactive oxygen species levels and inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha levels. Additionally, it enhanced superoxide dismutase and inhibitor of nuclear factor kappa B alpha levels, while lowering the expression of inducible nitric oxide synthase. Histopathological examination revealed significant improvements in gastric tissue morphology in GSS-treated groups compared to the control group. Molecular docking studies indicated potential interactions between GSS ethanolic extract compounds and various target proteins involved in oxidative stress, inflammation, and gastric protection in gastritis. This study aims to investigate the potential gastroprotective activity of GSS ethanolic extract against gastritis induced via pyloric ligation.