Marine natural products are a rich source of chemically diverse and biologically active molecules. Over two decades (2001–2024), a total of 228 marine natural products have been reported from soft corals, red algae, sponges and cyanobacteria collected in Malaysia. Malaysia is ranked as the 12th most biodiverse country in the world and is recognized as one of the world’s megadiverse nations. This chapter focuses on marine natural products isolated from these marine organisms, biological activities, sampling locations, compound isolation workflows, and 1H and 13C nuclear magnetic resonance (NMR) spectroscopy for structure characterizations. In addition, this chapter will also introduce some of the most prominent examples of marine natural products biosynthesis and origin of marine natural products.