Omega-3 fatty acids are long chain polyunsaturated fatty acids (LCPUFAs) have been the source of interest because of their beneficial pharmacological activities. These omega 3 LCPUFAs, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have shown anti-inflammatory activity, which increased the research interest on EPA and DHA for their possible effectiveness against cancer. EPA and DHA offer safe and non-toxic approach (as compared to anti-cancer drugs) to prevent or inhibit carcinoma cell growth. The present review article outlines research on omega-3 fatty acids on various carcinomas to understand the mechanism and effectiveness of EPA and DHA against different cancerous diseases. In this article, the increased interest in fish oil and the positive outcome of omega-3 fatty acids in the cancer research is highlighted. It suggests that the research on the natural compounds like omega-3 fatty acids should be encouraged to understand the mechanisms against tumor and to improve the quality of life.