The aim to study the phytochemical screening from Pistia stratiotes L. and Eichhornia crassipes (Mart.) Solms and analysis of components present in it by gas chromatography-mass spectrometry (GC-MS). The plant were sequentially extracted in different solvents viz., ethanol, methanol, ethyl acetate, petroleum ether, chloroform, acetone, hexane, aqueous, and 1%HCl. The ethanolic crude extract of weed, Pistia stratiotes L. and Eichhornia crassipes (Mart.) Solms showed different types of high and low molecular weight compounds by GC-MS analysis. n-Hexadecanoic acid (7.18%), E-11-Hexadecenoic acid, ethyl ester (1.04%), Hexadecanoic acid, ethyl ester (13.29%), L- Glutamine (0.38%), Linolelaidic acid, methyl ester (2.41%), 9,12,15-Octadecatrienoic acid, methyl ester,(Z,Z,Z) (2.7%), Palmitic acid (12.09%), Phytol (2.12%), 9,12-Octadecadienoic acid, ethyl ester(3.79%), Linolenic acid, ethyl ester (26.26%), Stearic acid, ethyl ester (0.98%), α-Glyceryl linolenate (1.35%), Diisooctyl phthalate (53.84%), Stigmasterol (11.39%), 1-Monolinoleoylglycerol trimethylsilyl ether(1.52%).

Most of the isolated and identified compounds by GC-MS in the crude extracts exhibit following bioactivities. Anticancer, Anti-inflammatory, Antimicrobial, Diuretic, Hepatoprotective, Anti-arthritic, Antiasthma, Antioxidant, Hypocholesterolemic, Nematicide, Pesticide, Lubricant, Anti-androgenic, Flavor, Hemolytic, 5-Alpha reductase inhibitor, Insectifuge, Antihistaminic, Anti-eczemic, Anti-acne, Anti-coronary, Antifouling effects so that they can be recommended as a plant of phytopharmaceutical importance. Therefore ethanol extract of Pistia stratiotes and E. crassipes proves as a potential source of bioactive compounds of pharmacological importance.