Marine ecosystem covers two-thirds of the earth’s surface, and is characterized by its rich biodiversity and endemism of marine life. However, like many other ecosystems, it has been subject to diverse anthropogenic pressures, such as climate change, pollution, and biodiversity losses. In the first part of the book, we discussed the pollution dynamics of the inorganic pollutants (heavy metals, metalloids) and organic pollutants including persistent organic pollutants (POPs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), microplastics, nutrients, and algal blooms in the marine environment. Marine pollutants can have a wide range of pollution sources that are able to cause deleterious effects on marine flora and fauna. The second section of the book specifically elucidates the toxicity assessment by using marine model organisms. It provides extensive new insight into screening biomarker genes combined with advanced gene editing applications. In the last section of the book, various remedial techniques, such as bioremediation and phytoremediation, were discussed whether it could be beneficial to deal with the challenges of marine pollution.