Several wild crops remain to be explored worldwide; among them, some have excellent medicinal and nutritional properties. In this study, Eleocharis dulcis has been selected for investigation of its chemical composition, nutritional values, total phenolic content, and antioxidant activity. The phytochemical constituents were screened by standard methods, indicating the presence of alkaloids, a-amino acids, carbohydrates, flavonoids, glycosides, phenolic compounds, polyphenol, reducing sugars, saponins, starch, and tannins. In a preliminary investigation by EDXRF, potassium, iron, chlorine, silicon, calcium, phosphorus, sulfur, manganese, bromine, copper, titanium, zinc, and rubidium elements were found in the EDXRF spectrum. It was found that potassium content is the highest among other elements. The nutritional values of the selected samples were determined by AOAC methods. The total phenolic content of aqueous extract (5.115 ± 0.05 mg GAE/mL) was determined by Folin-Ciocalteau assay. The antioxidant activity of aqueous extract was evaluated by the 2, 2-diphenyl-1- picryl-hydrazyl free radical scavenging assay. It possesses nearly the antioxidant activity of standard ascorbic acid. It is suggested that Eleocharis dulcis exhibits great potential for antioxidant activity, and it is useful for nutritional and pharmacological functions.