Benzimidazole derivatives are potential candidates for drug development. They are efficiently synthesized and possess various biological properties including antibacterial activity. A series of functionalized benzimidazole derivatives bearing N-(4-chloro- or fluorophenyl)pyrrolidin-2-one or N-(4-chloro- or fluorophenyl)aminobutanoic acid moiety were synthesized. Compounds possessing a very high antibacterial activity, comparable to that of a commercial antibacterial agent oxytetracycline, against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Bacillus cereus were identified. Some of the synthesized compounds exhibited significant antioxidant activity.