K. pneumoniae is a Gram-negative, nonsporogenic, immotile, rod-shaped bacterium that belongs to the Enterobacteriaceae family. It is widely distributed in the environment, the human digestive tract serves as its primary reservoir. Most infections caused by K. pneumoniae are opportunistic, healthcare-associated infections. The groups most at risk are infants, the elderly, and immunocompromised patients. However, a significant increase in hv strains and the emergence of new MDR clones have led to the emergence of infections in previously healthy individuals. K. pneumoniae has three main mechanisms of β-lactam resistance: enzyme production, efflux pump overexpression, and porin modification. Carbapenemase-producing strains are currently one of the most important nosocomial pathogens because they exhibit different resistance phenotypes and spread worldwide. They are resistant to most β-lactam antibiotics, quinolones, and most aminoglycosides. Therapeutic options are limited to reserve antibiotics: ceftazidime-avibactam and newer combinations with β-lactamase inhibitors, fosfomycin, colistin, tigecycline, selected aminoglycosides, as well as newer options such as plasomycin, eravacycline, and cefiderocol. The increase in colistin-carbapenem-resistant K. pneumoniae poses a serious public health threat, as resistance to colistin further limits therapeutic options. Also of concern is the emergence of resistance to new combinations of antibiotics with a β-lactamase inhibitor such as ceftazidime/avibactam. Appropriate infection control and antimicrobial stewardship programme are key to preventing the spread of resistance and extending the period during which new antibiotics are effective.