The phytochemicals found in Caralluma pauciflora were studied for their ability to reduce silver nitrate in order to synthesize silver nanoparticles (AgNPs) and characterize their size and crystal structure. Thunbergol, 1,1, 6-trimethyl-3-methylene-2-(3,6,9,13-tetram, Methyl nonadecanoate, Methyl cis-13,16-Docosadienate, and (1R,4aR,5S)-5-[(E)-5-Hydroxy-3-methylpent were the major compounds identified in the methanol extract by Gas Chromatography-Mass Spectrum analysis. UV/Vis spectra, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), SEM with EDAX, DLS particle size analyser and Atomic Force Microscope (AfM) were used to characterise the Caralluma pauciflora plant extract-based AgNPs. The crystal structure and estimated size of the AgNPs ranged from 20.2 nm to 43 nm, according to the characterization data. The anti-cancer activity of silver nanoparticles (AgNPs) synthesised from Caralluma pauciflora extract. The AgNPs inhibited more than 60% of the AGS cell lines and had an IC50 value of 10.9640.318g, according to the findings. The cells were further examined using fluorescence microscopy, which revealed that the AgNPs triggered apoptosis in the cells. Furthermore, the researchers looked at the levels of reactive oxygen species (ROS) in cells treated with AgNPs and discovered that the existence of ROS was indicated by green fluorescence. Finally, apoptotic gene mRNA expression analysis revealed that three target proteins (AKT, mTOR, and pI3K) were downregulated following AgNP therapy. Overall, the findings imply that AgNPs synthesised from Caralluma pauciflora extract could be used to treat human gastric cancer.