Natural products have been a key in modern drug discovery and development. Similarly, the sclareol molecule has been reported to show a huge number of biological applications. Because of sclareol's biological activity, we decided to test it as a potential drug candidate for treating gastric cancer in vitro. Proliferation and colony studies were performed with MTT and clonogenic assays. Apoptotic studies were performed with phase-contrast microscopy, Annexin-V/PI staining, DAPI staining, and western blotting. Phase distribution was tested with flowcytometry. Transwell assays were used to detect migration and invasion. Results discovered that sclareol possess time and dose reliant antiproliferative and anticolonogenic effects on SNU-1 cells (p < 0.05). The cellular and nuclear morphological investigations evidenced apoptotic cell death as they reported membrane blebbing, loss in integrity, chromatin condensation, nuclear shrinkage, apoptotic body formation and cytoplasmic shrinkage. Further, with the detection of enhanced activities of caspases-3, 8 and 9 and Bax and downregulated activity of Bcl-2, it was concluded that sclareol induced apoptosis in SNU-1 cells. Phase distribution of cell cycle showed blockade at G0/G1 phase in treatment group. The antimetastatic effects of sclareol were detected in SNU-1 cells as it inhibited their ability to migrate and invade. Overall, sclareol targeted multiple aspects of gastric cancer, including cell morphology, apoptosis, cell migration, invasion, and cell cycle.