The book "Bio-activities of Turbinaria ornata and its silver nanoparticles" offers a comprehensive examination of the biological properties of five species of algae collected from the coast of Rameshwaram, Tamil Nadu. Various extracts, including methanol, hexane, and acetone, from the marine algae Sargassum plagiophyllum, S. fusiforme, S. wightii, S. falciparum, and Turbinaria ornata were tested for their antibacterial activity against four multidrug-resistant bacterial strains. Notably, the hexane extract of T. ornata exhibited the highest activity against Staphylococcus aureus, Klebsiella sp., and Pseudomonas aeruginosa. Additionally, the synthesis of silver nanoparticles from the aqueous extract of T. ornata is described, which were analyzed using various characterization methods such as UV-Vis spectroscopy and FESEM. The book also discusses the larvicidal effect of the hexane extract and silver nanoparticles on two larval species of Aedes aegypti and Culex quinquefasciatus, as well as their potential anti-cancer properties.