Highly contaminated municipal wastewater is being disposed of into land and rivers without any prior treatment has severe side effects on human and marine animals. This research focused on the treatment of Majeed Keerio village municipal wastewater through horizontal flow constructed wetland system. The experimental study was evaluated and monitored timely over a year. The overall treatment efficiency performance of the wetland system was determined by considering organic pollutants removal efficiency. This study emphasized on the design of horizontal flow constructed wetland for the effective treatment of municipal wastewater of village Majeed Keerio, Sakrand, Sindh. The constructed wetland efficiently reduced COD, BOD 5 , TSS, turbidity, total phosphate, total nitrogen pollutants of wastewater, which was about 92.3%, 93%, 96%, 96.4% and 74%, respectively. This method reduced all thermotolerant coliforms. Constructed wetland system was found most economical and effective for the treatment of domestic wastewater. The effect of different hydraulic loading rates under varying hydraulic retention times within the constructed wetland was examined. The higher hydraulic retention times resulted in improved pollutants removal efficiency.