This study explores the use of Lemna minor, a free-floating aquatic plant, for phytoremediation of municipal wastewater from Chhatrapati Sambhajinagar, Maharashtra. Conducted over four months (April–July 2023), the experiment involved treating wastewater at varying concentrations (20% to 100%) using 200 g of fresh Lemna minor in controlled cement tanks. Key water quality parameters—such as pH, electrical conductivity (EC), total suspended and dissolved solids (TSS and TDS), biochemical and chemical oxygen demand (BOD and COD), along with nutrients like nitrates, phosphates, sulphates, chlorides, and nitrogen compounds—were analyzed before and after treatment. The results indicated significant improvement in water quality. pH levels moved closer to neutral (6.5 to 7.2), and EC decreased by up to 497 µS/cm. Notable reductions were recorded in TSS (up to 59 mg/L), TDS (58 mg/L), BOD (60.8 mg/L), and COD (141 mg/L). Additionally, nutrient removal was effective, with significant decreases in nitrate, phosphate, ammoniacal nitrogen, and total nitrogen-helping to mitigate eutrophication risks. The findings confirm Lemna minor’s capacity to absorb both organic and inorganic pollutants, demonstrating its potential as a cost-effective, sustainable, and environmentally friendly solution for wastewater treatment. While results are promising, further optimization is recommended for handling higher pollutant loads. This study highlights phytoremediation as a viable green alternative to conventional wastewater treatment methods.