Oscillatoria limosa is a well-known member of blue-green algae, usually found in open water reservoirs. Ecologically it plays very important roles, like releasing Oxygen and being a supportive alternative source of food for aqua fauna. In research, it is being investigated as a medicinal organism for cancer and infectious diseases. In the current study, we have determined the medicinal and ecological importance of Oscillatoria limosa particularly found in the vicinity of district Jamshoro 76080, Sindh, Pakistan. For this purpose, four different solvent extracts of 20% (w/v) dried powder of organism were used to determine the presence of bioactive compounds, phytochemicals, antimicrobial activities, and antioxidant properties through previously well-reported methods. The obtained results of this study prove the presence of phenolic acid, flavonoids, total proteins, total sugar, reducing sugar and one free amino acid, and phytochemicals like alkaloids, phytosterol, tannin, terpenoids, glycosides, and saponin in samples. In this study, remarkable antioxidant properties ranging from 0.248 to 1.080 mg ml -1 were observed in all the samples. The antibacterial activities against S. aureus, A. tumefaciens, K. aureus, E.coli, and P.aeruginosa, and antifungal activities against A. niger, P. notatum, and Rhizopus were observed, which proves it a good antimicrobial organism. It may be concluded from this study that Oscillatoria limosa of local vicinity is a potential organism of interest for biotechnological and pharmaceutical industries as an antitumor, antimutagen, free radical scavenger, and possess antimicrobial properties against various kind of bacteria and fungi.