Sesamin is the major active ingredient is Sesamum indicum seeds. Several studies revealed that sesamin possesses potent anti-cancer properties. The anti-cancer effects of sesamin have been mainly attributed to its anti-proliferative, pro-apoptotic, anti-inflammatory, anti-metastatic, anti- and pro-angiogenic, and pro-autophagocytic activities. In this review, we provide a comprehensive summary of the reported anti-cancer effects of sesamin, both in vitro and in vivo. Experimental findings related to the potential of sesamin to attenuate oxidative stress, inflammation, proliferation, metastasis, and angiogenesis in various cancer cells and tumors are analyzed. Studies focusing on the ability of sesamin to induce apoptosis and autophagy in cancer cells are also underscored. Moreover, the molecular mechanisms underlying the anti-cancer effects of sesamin are highlighted, and the major signaling pathways targeted by sesamin are identified. Although the exact signaling events triggered by sesamin in cancer cells are not fully revealed, our analysis indicates that NF-κB, STAT3, JNK, ERK1/2, p38 MAPK, PI3K/AKT, caspase-3, and p53 signaling pathways are critically involved in mediating the anti-cancer effects of sesamin. In sum, the experimental evidence suggesting that sesamin could exert potent anti-cancer activities in vitro and in vivo is compelling. Hence, sesamin can potentially be employed as an effective adjuvant therapeutic agent in ameliorating tumor development and progression, and therefore, it could be used in the prevention and/or treatment of various types of cancer.