Major marine natural products (MNPs) and marine organisms include sea urchin, sea squirts or ascidians, sea cucumbers, sea snake, sponge, soft coral, marine algae, and microalgae. As vital biomedical resources for the discovery of marine drugs, bioactive molecules, and agents for treatment of infectious diseases and major non-communicable diseases (mNCDs), these MNPs have bioactive potentials of antioxidant, anti-infection, anti-inflammatory, anticoagulant, anti-diabetic effects, cancer treatment, and improvement of human immunity. This article reviews MNPs as huge and novel biomedical resources for anti-infection of coronavirus, SARS-CoV-2 and its major variants (such as Delta and Omicron), as well tuberculosis, H. Pylori, and HIV infection, and as promising biomedical resources for infection related cardiovascular disease (irCVD), diabetes, and cancer. The anti-inflammatory mechanisms of current MNPs against SARS-CoV-2 infection are also involved. Moreover, since the use of other chemical agents for COVID-19 treatment are associated with some adverse effects in cardiovascular system, MNPs have more therapeutic advantages. Herein, it’s time to protect this ecosystem for better sustainable development in the new era of ocean economy, since MNPs are indeed huge, novel and promising biomedical resources for anti-infection of SARS-CoV-2 and its major variants as well as irCVD. The novel potential mechanisms may be through multiple targets and pathways regulating human immunity and inhibiting inflammation. In short, MNPs are worthy of translational research for further clinical application.