Zinc oxide nanoparticles represent an alternative to implement efficient measures to inhibit the growth of various microorganisms, especially bacteria like Klebsiella pneumoniae. The present investigation aims to determine the minimum inhibitory concentration of zinc oxide nanoparticles on the growth of Klebsiella pneumoniae ATCC 700603 producer of extended spectrum beta-lactamases (ESBL+). For this, zinc oxide nanoparticles were synthesized and provided by the Multidisciplinary Research Laboratory of UPAO. Then, the strain of Klebsiella pneumoniae ATCC 700603 was reactivated and its average logarithmic phase and generation time were determined. To determine the Minimum Inhibitory Concentration (MIC), the technique of macrodilution in broth was used in 10 experimental sterile tubes with Müller Hinton broth at different concentrations of ZnO nanoparticles, to which a suspension of the ba...