Noyyal River is one of the highest polluting rivers in India and heavy metals present in river water is out of standard level. The effluent water of textile industries and spinning mills present in Trippur district discharged into the Noyyal River which polluted the Noyyal river. Because of this contamination affects the crop yields and human health. But purification of River Noyyal by using physical and chemical methods are highly expensive and complicated. In this study phytoremediation technology used for the purification of Noyyal river. Lesser Indian reedmace (Typha angustifolia) serve as a phytoremediation plant which helps in the cleaning up of contamination from the polluted river. The test results show that after phytoremediation treatment COD, BOD, cadmium, chromium, lead, zinc, copper and mercury level gradually reduced within 0 to 15 days interval. Lesser Indian reed mace plant easily grows in the banks of the river. If plantation of Lesser Indian reedmace planted in banks of the river which helps on the removal of heavy metals present in the water gradually. From the result, it can be concluded that the phytoremediation technology is suited for purification of Noyyal river.