Sewage treatment is a critical process that ensures the safe disposal and management of wastewater generated from households, industries, and commercial establishments. The treatment process involves various physical, biological, and chemical methods to remove contaminants and pollutants from sewage before it is released back into the environment or reused. Among these methods, the use of chemicals plays a significant role in enhancing the efficiency of sewage treatment. This article explores the various chemicals used in sewage treatment, their functions, and the overall impact on the treatment process.