This study investigates the biochemical constituents, preliminary phytochemical composition, and antibacterial potential of the freshwater alga Hydrodictyon reticulatum (Linnaeus) Bory. Biochemical analysis revealed carbohydrate content of 11.60 mg, protein content of 27.67 mg, chlorophyll content of 0.39 mg, amino acid content of 11.00 mg, and total phenolic content of 15.67 mg. Phytochemical screening identified the presence of alkaloids, flavonoids, tannins, phenolic compounds, partial lignin, and glycosides.