With th e massive use of antibiotics ，Klebsiella pneumoniae has shown a trend of multiple drug resistance ， especially carbapenem-resistant K. pneumoniae ，which means that fewer and fewer antibiotics can be used to treat K. pneumoniae infection. Polymyxin has become the last line of defense for the treatment of carbapenem-resistant K. pneumoniae infection due to its unique antibacterial mechanism. However ，with the increase of its use ，the reports of drug-resistant K. pneumoniae strains at home and abroad are also on the rise ，seriously endangering the lives of patients . The author summarizes the resistance mechanism of K. pneumoniae to polymyxin ，and find that the resistance mechanism of K. pneumoniae to polymyxin mainly includes the structural modification of lipopolysaccharide in bacterial outer membrane ，the overexpression of capsular polysaccharide and the overexpression of multidrug efflux pump ，which can provide a basis for the rational use of the drug and the prevention and treatment of drug-resistant K. pneumoniae .