Objective: Global statistics revealed that respiratory tract infections (ARTIs) are one of the main causes of mortality. Klebsiella pneumonia is considered one of the main causes of ARTIs. Levofloxacin has a wide spectrum effect against gram negative and gram positive bacteria, and its inhibitory activity can by improved through nanobiotechnology. Method: A nanohybrid antibiotic was synthesized by intercalating levofloxacin between magnesium oxide layers. The prepared antibiotic was characterized by fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM) and atomic force microscope (AFM). Results: FT-IR spectrum showed the appearance of new groups in the Lev-MgO spectrum, which indicate the creation of a new compound. XRD spectrum revealed the presence of new diffraction planes which support the results obtained from FT-IR technique. SEM images demonstrated that MgO particles were converted to structure similar to coins arranged in irregular mode. AFM images showed the formation of spherical nanoparticle that indicates the formation of a new compound. Conclusion: The nanohybrid antibiotic was efficient in inhibiting twelve Klebsiella pneumonia isolated from respiratory tract infections.