Water, the most valuable gift of nature is at a critical stage so called pollution, due to intense industrialization,
urbanization and exponential population growth. Thus, a diagnosis that has the potential to cure that critical stage of water with no harmful impact on the other elements of nature is an utmost requirement now a days. Tremendous development in the field of research has suggested a number of treatment methods to get over water pollution. Constructed wetland (CW) an engineered unit that follows bio-geochemical approaches to heal the polluted stage of water with a significant pollutant removal efficiency, has stood first in the field of sustainable water treatment and technology. Not only water treatment through an eco-friendly manner but also creating an ecosystem with in that working area with aesthetic and economical production are the major reasons behind the popularity of this system. Selection of vegetation, substrate and construction of that system at a proper location are the limitation of constructed wetland. In this system sedimentation, filtration and adsorption through substrate, neutralization, and precipitations, phyto-accumulation of plant species and microbial remediation by microorganisms present in the rhizospheres of plants etc. are the processes that supports the treatment activity. This paper discusses various types of constructed wetlands and their mechanism and performance intended for municipal wastewater treatment. Besides it the paper covers the discussion regarding reusability of the treated water. This paper will help promote the wastewater treatment using CWs
and further help to design and develop innovative hybrid technologies for sustainable wastewater treatment.