Background The predisposition toward gastrointestinal disease is increasing as a result of dietary changes and overindulgence in food preparation. Ninety percent of stomach cancers are adenocarcinomas, a type of cancer of the gastrointestinal tract that is the leading cause of mortality worldwide. Purpose Astilbin, a natural dihydroflavonol substance derived from a range of foods and medicinal herbs, has been shown in the current study to have anticancer potential against gastric cancer in AGS cell lines. Methods The half maximal inhibitory concentration value was determined after astilbin was given to AGS cell lines at various doses. To verify apoptosis, the astilbin-treated cell line was subsequently stained with the dual dye acridine orange/ethidium bromide. AGS cell lines, the enzyme-linked immunosorbent assay (ELISA) approach was also used to investigate the inflammatory cytokines. Using ELISA, apoptotic marker expression including Bcl-2-associated X-protein, caspase-9 proteins, and B-cell lymphoma 2 was assessed in gastric cancer cells treated with astilbin. Results The study’s findings reveal that astilbin is a prime candidate for gastric cancer therapy since it causes apoptosis in AGS cells and has a stronger effect on the major inflammatory markers of the disease. Conclusion The study provides comprehensive methodologies and tools for predicting absorption, distribution, metabolism, excretion, and toxicity properties, facilitating informed decision-making in the development and optimization of astilbin as a gastric cancer therapy.