Involves synthesis of Schiff bases (hydrazone) by the reaction of acid hydrazide(D1) (which is prepared from the reaction of cyanoethyl acetate with hydrazine hydrate at (85%) with aromatic aldehydes to obtain compounds (D2-6) and by the reaction of compounds (D2-6) with phthalic anhydride Compounds (D7-11) are obtained, the biological activity of the prepared compounds is studied through two types of Gram-positive and Gram-negative bacteria Staph. aureus, Escherichia Coli and Compare it with one type of antibiotic (Gentamycin). The validity of the structures is confirmed by spectroscopic methods (FTIR, 1H-NMR, 13C-NMR, MASS). The disk diffusion assay technique was used to investigate the antibacterial activity in vitro against two types of bacteria: gram-positive and gram harmful bacteria. The minimum inhibitory concentration [MIC] was measured using standard medications. The findings revealed that azetidine derivatives outperformed drugs in inhibiting the growth of both gram-positive and gram-negative bacteria.