In our study, compared to untreated controls, Bax, caspase-3, and caspase-9 protein expressions were dose-dependently upregulated and anti-apoptoticBcl-2 downregulated with the Z-ajoene treatment, which supports an apoptotic effect of Z-ajoene against NSCLC A549 and H1299 cells. Here, CASP9 is linked to non-small cell lung carcinoma.