In order to analyse the evolution of the sensitivity to antibiotics of same strains with nosocomial potential such as Klebsiella isolated in a hospital, we took into study a number of 976 samples, collected in a new-born care department of the "Dr. D. Popescu" hospital Timişoara. The study took place between November-December 2002. The collected samples were pharyngeal swabs, nasal swabs, gastric aspirates, ocular and umbilical secretions, vernix, urines, faeces and blood. From all these samples 803 strains with nosocomial potential were isolated, 84 strains being Klebsiella spp. Most of the isolated strains presented multiple phenotypes of resistance to antibiotics.