Lannea acida is a plant known to have various medicinal and therapeutic properties. The phytochemicals or secondary metabolites and antibacterial activity of its root and stem bark were studied in this research work. The phytochemical screening of the plant revealed the presence of bioactive components comprising flavonoids, alkaloids, saponins, steroids, terpenoids, glycosides and phenols while tannins were not detected in both the root and stem bark of the plant. The plant extracts was subjected to antibacterial activities against E. coli, S. aureus and Shigella spp to confirm its medicinal and therapeutic properties using various concentrations range 50 mg/mL – 6.25 mg/ml. From the study it was observed that the stem bark extract has the highest antibacterial activity against E. coli and Shigella spp with zone of inhibition of 18.50 ± 0.02 and 14.10 ± 0.12 mm while the root recorded the highest antibacterial activity against S.aureus with zone of inhibition of 16.37 ± 0.07 mm. The result indicates that the extracts of root and stem bark of this plant possess antibacterial activities.