Salvia species are used as food and medicinal plants all around the world. In this study, chemical composition and antimicrobial, toxicity, antioxidant, and enzyme inhibitory activity of Salvia nemorosa were evaluated. Phenolic components were characterized by the HPLC-DAD and 11 components were identified, in which rosmarinic acid was detected as the major compound (7584 μg/g extract). Sixteen volatile components were determined in both leaves and flowers essential oils. Oxygenated sesquiterpenes were the major components. Methanolic extract showed the highest total phenolic and flavonoid contents (294 mg GAE/g and 117 mg QE/g extract, respectively) and the strongest DPPH radical scavenging activity (IC50: 82 μg/mL). Plant samples showed moderate to high aldehyde oxidase, xanthine oxidase, acetylcholinesterase, and α-glucosidase inhibitory activity and moderate cytotoxicity. Also, EOs exhibited great antimicrobial potential (IZ: 8.8–33.7 mm). Our findings indicated that S. nemorosa may be useful for novel applications in functional food and pharmaceutical industries.