In this study, resistance of Klebsiella pneumoniae (K. pneumoniae) to PB was induced by passaging in serial concentrations of PB. This study employed TMT-labeled quantitative proteomics and LC-MS/MS metabolomics analysis to investigate the key biological processes associated with PB resistance in K. pneumoniae. A total of 315 differentially expressed proteins (DEPs) were identified, of which 133 were upregulated, and 182 were downregulated in the PB resistant K. pneumoniae. Metabolomics data demonstrated that 23 metabolites were significantly upregulated in PB resistant K. pneumoniae, 5 were downregulated.