Glioblastoma (GB) is a highly aggressive brain tumor with limited treatment options. This current study assessed the cytotoxicity of six phytocompounds—colchicine, piperine, quercetin, theobromine, reserpine, and cineole—on LN229 and U-87 MGGB cell lines using MTT assay. Colchicine demonstrated potent cytotoxicity through microtubule disruption and oxidative stress modulation, while quercetin exhibited broad-spectrum activity, including apoptosis induction and chemosensitization. Reserpine selectively targeted GPCRs, reducing cell invasiveness and angiogenesis. Theobromine, cineole, and piperine showed limited direct cytotoxicity but displayed unique interaction profiles suggesting complementary therapeutic roles. Enrichment analysis highlighted pathways critical to GB, such as ROS metabolism and MAPK signaling. These findings underscore the potential of phytocompounds as standalone or combinatorial therapies for glioblastoma, warranting further in vivo and mechanistic studies.Colchicine, reserpine, and quercetin show promise as glioblastoma treatments due to their complementary mechanisms of action, warranting further in vivo studies and mechanistic exploration to confirm their clinical potential.