Mangrove forests are salt tolerant plants confined to the coastal areas and occupy only 5% of the total forest areas of the world. These are the most hostile environment with fluctuating tidal and saline regime and a limited plant species can survive under such condition. Nevertheless, these plants are most valuable resources and provide economic and ecological benefits to the coastal people. Several mangrove species have been used in traditional medicine or have few applications as insecticide and pesticide. Mangroves are biochemically unique, producing wide array of natural products with unique bioactivity. They possess active metabolites with some novel chemical structures which belong to diverse chemical classes such as alkaloids, phenol, steroids, terpenoids, tannins, etc. The present review examines recent investigations on the biological activities of extracts and phytochemicals identified from mangroves and their associates as antimicrobial, antiviral, antioxidant, anticancer and many other properties like antiproliferative, insecticidal, antimalarial, antifeedant, central nervous system depressant and anti-plasmodial etc. The present article also emphasizes and creates an awareness of potential mangroves and their associates as a source of novel medicines, agrochemicals and source of many biologically active compounds.