Cymbopogon citratus (lemon grass) is an important species of Poaceae family. Lemongrass constitute various organic compounds and were reported to possess high medicinal potential. It has been used as traditional medicine for treatment of several diseases such as fever, sore throats, cough, laryngitis, bronchitis, oral candiasis, body ache, head ache, digestive problems etc. This study aimed to extract Cymbopogon citratus leaf using water as solvent with view to determine the phytochemical constituents followed by qualitative analysis by Thin Layer Chromatography. Phytochemical analysis revealed the presence of several bioactive compounds such as flavonoids, phenols, tannins, alkaloids etc. And TLC analysis further confirmed the presence of those secondary metabolites. The study revealed the presence of bioactive molecules in water extract in lemongrass.