Saccharum spontaneum Linn., a perennial grass, is valued in traditional medicine and sugarcane breeding. This study examined the chemical makeup of its ethanolic leaf extract and tested its antibacterial, antidiarrheal, and antidepressant effects on Wistar albino rats, with ethical approval. Antidiarrheal effects were assessed after castor oil-induced diarrhea, CNS depressant activity via actophotometer tests, and antimicrobial activity using the agar disc diffusion method against various bacterial and fungal strains. FTIR analysis of Saccharum spontaneum Linn. leaf extract showed characteristic absorption bands indicating the presence of polyols and aromatic rings. In the castor oil-induced diarrhoea experiment, the ethanolic extract significantly reduced diarrhoea in rats, demonstrating strong antidiarrhoeal effects, with 80.74% and 84.74% inhibition at 200 mg/kg and 400 mg/kg doses, respectively, outperforming the standard drug loperamide. The ethanolic extract of Saccharum spontaneum Linn. leaves exhibited significant CNS depressant activity, reducing locomotor activity in rats. It also showed moderate antibacterial activity, particularly against Staphylococcus, and strong antifungal activity with an 18 mm inhibition zone against Candida albicans