A series of bis-[1,5]-benzothiazepines (3a-e) were synthesized by base catalyzed reaction of bis-chalcones (1a-e) with two equivalent of 2-aminothiophenol (2). All the synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral analysis. The synthesized compounds were evaluated for their in vitro antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherchia coli, Pseudomonas aeruginosa and showed significant antibacterial activity.