The mangrove ecosystem is seen as a desirable hotspot for biodiversity and is being extensively researched in the hopes of finding novel, practical chemical scaffolds, possibly with therapeutic uses, including anticancer properties. Over the years, microorganisms derived from mangroves demonstrated to be abundant sources of bioactive secondary metabolites, by the steady increase of publications, indicating the enormous potential of this significant ecological niche. This chapter aims to illustrate how anticancer agents and medicines are discovered and developed from mangrove sources. Since ancient times, the foundation for the therapy of human ailments has been natural chemicals derived from marine species and mangrove bacteria. Natural compounds are valuable sources of novel pharmaceuticals and can also be used as models for synthetic alteration. Numerous effective anticancer medications already in use have natural sources or equivalents, and numerous others are undergoing clinical studies. The purpose of this chapter is to draw attention to the essential contribution that natural products derived from mangrove microbiome have made and continue to make in the quest for anticancer drugs.