The study was aimed to investigate the phenolic compounds of Allium macrochaetum by LC-MS/MS, as well as the antioxidant, antialzheimer, and antimicrobial activities of the extracts, and determination of the essential oil and fatty acid compositions by GC-MS. The results indicate that malic acid and t-caffeic acid are the major compounds in the bulbs. The main components of fatty acids were found to be linolenic (40.72%), oleic (19.79%), and palmitic (18.45%) acids. The allyl disulfide (66.97%) was found as major compound in the essential oil. The ethanol extract of the bulbs exhibited stronger ABTS cation (IC50: 55.90 ± 1.08 µg/ml) and DPPH free (IC50: 204.43 ± 2.17 µg/ml) radical scavenging activities than the other extracts. The extract also showed moderate cupric reducing activity with 1.52 absorbance at 100 µg/ml concentration. Only the ethanol extract of the bulbs showed weak inhibition (23.34 ± 0.11%) against butrylcholinesterase enzyme at 200 µg/ml. Practical applications: Allium macrochaetum is a wild and edible garlic species which grown in Turkey, Iran, Iraqi, and Syria. A. macrochaetum has been used by local people in Turkish folk medicine as an antibiotic, and for the treatment of alopecia. The health benefits and nutritional values of A. macrochaetum were clarified in the first time. Phenolic compounds of A. macrochaetum were detected by LC-MS/MS. The essential oil and fatty acid compositions of A. macrochaetum were identified by GC-MS. Antioxidant, antialzheimer, and antimicrobial activities potential of A. macrochaetum were determined.