Klebsiella pneumoniae and Klebsiella oxytoca are opportunistic pathogens frequently isolated from infections in animals and humans. In animals, they can cause septicemia, urinary and respiratory infections and mastitis. In humans, these microorganisms may also be the cause of nosocomial infections. The aim of the study was determination of the presence of K. pneumoniae and K. oxcytoca in invasive turtle species, as a vector of pathogenic microorganisms for other animals and humans. Examined material originated from twenty five turtles of invasive species, belonging to all subspecies of Trachemys scripta (red-eared slider, Cumberland slider, yellow-bellied slider). For examinations, swabs from live animals and internal organs during necropsy were collected. Samples were cultured on MacConkey agar. Suspected colonies were identified on the basis of morphology, biochemical properties and using molecular biology methods. PCR assays according to Chandler et al. (2011) for the presence of genes gyrA, rpoB, pehX allowed identification of examined strains as the genus Klebsiella and the species K. pneumoniae and K. oxytoca. Seventeen strains of K. pneumoniae and nine strains of K. oxytoca were isolated from examined samples. The studies showed the presence of potentially pathogenic microorganisms of the genus Klebsiella in invasive turtle species. This work was supported by the National Science Centre project “Invasive turtle species as a source and vector of animal and human pathogens” (Grant No. 2013/11/B/NZ7/01690).