Minocycline hydrochloride is a broad-spectrum antibiotic, effective against tetracycline sensitive or resistant Staphylococcus aureus;It has a slightly stronger effect on Staphylococcus green, Actinomycetes astratus, Dipneumococcus pneumoniae and bacteria-like microorganisms, Neisseria gonorrhoeae than other tetracyclines, and has a similar antibacterial strength to tetracyclines on Escherichia coli, Proteus, Salmonella, Shigella, Klebsiella, Pseudomonas.