In this work, the aerial parts of Cymbopogon citratus, harvested in Algeria, were analyzed as potential sources of biologically active compounds. The phytochemical composition, the content of total phenols and flavonoids in the methanolic extract of this plant, as well as its antioxidant, antibacterial, and antifungal capacities, were evaluated. The methanolic extract had phenolic compounds and flavonoids, with levels of 92.82µg GAE/mg Dry weight and 58.98µg QE/mg Dry weight, respectively. Furthermore, the methanolic extract exhibited moderate antioxidant activity as assessed by DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'azinobis (3-ethylbenzothiozoline-6-sulfonic acid) disodium salt radical), and β-carotene tests, while its antimicrobial activity was tested against four bacterial strains. Thus, a MBC/MIC ratio of 2 indicates that the extract exhibits bactericidal activity against Escherichia coli. Additionally, the extract exhibited antifungal activity against Thielaviopsis paradoxa, Alternaria sp., and Fusarium solani, with inhibition rates ranging from 50.59% to 70.20%. LC-MS analysis identified a variety of components, including chlorogenic acid (17.40%), catechin (34.64%), salicin (9.55%), and curcumin (8.97%), which are likely responsible for the observed activities. This study demonstrated that the aerial parts of Cymbopogon citratus offer a cost-effective source of natural compounds with bactericidal and antifungal activity, offering potential applications in the food and pharmaceutical industries.