N-(4-(1H-Benzo[d]imidazol-1-yl)phenyl)-3-nitrobenzamide,N-(4-(1H-benzo[d]imidazol-1-yl)phenyl)-4- chlorobenzamide, 4-(1H -benzo[d]imidazol-1-yl)benzenamine and N-(4-(1H-benzo[d]imidazol-1-yl)phenyl)-4-bromobenzamide were synthesized and characterized by IR and NMR techniques. These N-substituted benzimidazole derivatives were screened for their antibacterial activity by Well diffusion method against Bacillus subtilis (B. subtilis), Staphylococcus aureus (S. aureus) (Gram-positive) and Escherichia coli (E. coli), Klebsiella (Gram-negative) bacterial strains. The com-pounds tested were found to have good antibacterial activity against all bacteria. The antifungal activity of the compounds was tested against Aspergillus flavus (A. flavus) and Aspergillus Niger (A. Niger) fungal strains. Antifungal results indicated that 4-(1H -benzo[d]imidazol-l-yl)benzenamine and N-(4-(1H -benzo[d]imidazol-1-yl)phenyl)-4-bromobenzamide derivatives showed better activity than the reference drug. © 2015 Scientific Publishers. All Rights Reserved.