Wetland is effective in removing organic matter, TSS, phenols and nutrients. The wetland effluent met the European Union discharge guideline. Plant, Phragmite plays a significant role in removing nutrients and TSS. The removal efficiency of the wetland for ammonia and nitrate was very weak during the early stage of the wetland but increase as the wetland gets mature. This study was mainly focused on optimization of nitrogen removal using nitrification-denitrification path way in vertical flow constructed wetlands. The ZIN conference center wetland improve the removal efficiency of nutrients by increasing the water level of the effluent. After the wastewater in ZIN conference center is treated by wetland system, the canal water around it decreases the eutrophication of the water bodies. This was one important indicator of the treatment efficiency of wetland.