Abstract: A remediation system based on pollution obstruction for underground water with DNAPL pollutant is provided, including a vertical obstructing wall, a pump-out treating unit and a recharging unit, wherein the vertical obstructing wall is distributed at the periphery of a polluted area to obstruct the polluted underground water in the vertical obstructing wall; the pump-out treating unit includes a plurality of water pumping wells and overground treatment facility that are distributed in the polluted area, the plurality of the water pumping wells are configured to pump the polluted underground water out and sending it into the overground treatment facility so as to be treated; the recharging unit includes a plurality of recharging wells, and water treated by the overground treatment facility is recharged into a target aquifer in the polluted area by the plurality of the recharging wells. A remediation method using the system is provided.