Some 6,8-dichloro-quinolone compounds were designed and synthesized; by comparing with 6-fluoro-8-chloro-quinolone compounds, the influence of the nature of the halogen atom from six position of the quinolone ring on the molecular properties and on the antimicrobial activity was studied. The DFT/B3LYP/6-311G* level of basis set was used for the computation of molecular structure of optimized compounds. The calculations of characteristics and molecular properties were performed using Spartan�14 Software from Wavefunction, Inc. Irvine, CA. The HOMO-LUMO energies and orbitals, global reactivity descriptors, various thermodynamic parameters, and dipole moment (i) were calculated to determine the molecular properties of quinolone compounds. Molecular docking studies were realized to identify and visualize the most likely interaction ligand (quinolone/fluoroquinolone compounds) with the protein receptor. The score and hydrogen bonds formed with the amino acids from group interaction atoms are used to predict the binding modes, the binding affinities, and the orientation of the docked quinolone/fluoroquinolone derivatives in the active site of the protein receptor. The protein-ligand complex was realized based on the X-ray structure of Bacillus cereus (PDB ID: 1VEN) using CLC Drug Discovery Workbench 2.4 software. The quinolone compounds were characterized by physical-chemical methods (elemental analysis, IR spectral analysis, 1H-NMR, 13C-NMR spectra, UV-Vis, thin layer chromatography) and by antimicrobial activity against some Gram-positive and Gram-negative microorganisms: Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Micrococcus luteus, Escherichia coli and Pseudomonas aeruginosa.