Epidemiological and laboratory studies provide insight into the anti-carcinogenic potential of garlic and its constituent compounds. Garlic is appealing as an anti-carcinogenic agent due to its ability to induce apoptosis in vitro. Diallyl disulfide (DADS) is one of the major components of garlic that used to determine inhibition of cell proliferation and induced apoptosis in human colon cell lines. In this study, human colorectal cancer cell lines (LOVO, HCT-116, SW-480) were exposed to DADS. The inhibitory effects of DADS dose level more than $50;{mu}M$ in the cell viability of all cell lines. Cell growth activity inhibits of human colon cancer cell lines. The inhibitory effects of DADS dose level more than $25~50;{mu}M$ in the cell growth using MTT assay. We found that DADS may have the apoptosis action (chromatin condensation, DNA fragmentation) using DAPI staining and increased the expression of caspase-3 at the dose level more than $100;{mu}M$, decreased the expression level of $eta-catenin$ at dose dependent in the western blotting. We suggest that DADS may have a potential candidate as cancer chemopreventive agents.