Brucellosis is caused by an intracellar pathogens called Brucella. It is a zoonotic disease because it has impoverished many people all over the world. It is responsible for renal and cardiac failures in human beings. Tetracycline is one of the prominent antibiotics employed as anti-brucella agent. Therefore, herein the potency of some tetracycline molecules for combating Brucellosis was investigated by molecular docking of the protein responsible for the disease and tetracycline molecules. We calculated several DFT reactivity descriptors for five Tetracycline molecules as anti-brucellosis at the B3LYP/6–311++G(d,p) level of theory in order to analyze their reactivity in vacuum and solvent phases. DFT-based descriptors was determined to predict the reactivity of Tetracycline molecules.  The inhibition based on the binding affinity values showed that inhibition was in the order: Anhydrotetracycline >Metatetracycline > Oxytetracycline > Tetracycline > Chlorotetracycline. Therefore, among the five tetracycline molecules studied, Anhydrotetrcycline is the most effective antibiotics for combating Brucellosis.