Rapid resistance to chemotherapeutic drugs has opened a new venue for using natural products toward novel designs of drug formulations. Naturally occurring compounds and pigments from cyanobacteria have numerous applications in human health, including cancer treatment. These photosynthetic prokaryotes produce secondary metabolites with antitumor and antiinflammatory properties leading to advancements in the development of a wide range of drugs exploited by the pharmaceutical industry. Bioactive and chemically diverse compounds such as cyclic peptides, lipopeptides, fatty acid amides, alkaloids, and saccharides produced by cyanobacteria have induced apoptosis in cancer cell lines. In addition, carotenoids and phycobiliproteins from these organisms have antiinflammatory and anticancer properties. These compounds also serve to develop synthetic analogs with improved bioactivity and have successfully entered clinical trials. This review focuses on the various bioactive compounds from cyanobacteria, their anticancer properties, processing, and mechanisms of action. © 2022 Elsevier Inc. All rights reserved.