Nitrogen removal is a critical process in wastewater treatment to reduce the presence of excess nitrogen compounds, such as ammonia and nitrate, which can negatively impact the environment if released untreated. This process is essential in preventing eutrophication of water bodies, which can lead to harmful algal blooms and oxygen depletion in aquatic ecosystems. There are several methods used for nitrogen removal in wastewater treatment, including biological processes such as nitrification and denitrification, as well as physical and chemical methods like adsorption, ion exchange, and membrane filtration. Each method has its own advantages and limitations, and the most appropriate technique depends on factors such as the level of nitrogen in the wastewater, the desired effluent quality, and the available resources. Overall, nitrogen removal is an important research area in environmental engineering and wastewater treatment, as it plays a crucial role in protecting water quality and ecosystem health. Ongoing research in this area focuses on developing more efficient and cost-effective nitrogen removal technologies, as well as understanding the impacts of nitrogen pollution on human health and the environment.