Klebsiella pneumoniae is an important opportunistic pathogen associated with multidrug-resistant infections in humans and animals. In this study, we performed a global proteomic analysis of the isolate JX21CTR26 to characterize its whole-cell protein expression profile. Bacterial cells were cultured under standard laboratory conditions, and total proteins were extracted, digested with trypsin, and analyzed by high-resolution LC–MS/MS. The resulting dataset provides a comprehensive catalog of proteins expressed by K. pneumoniae JX21CTR26 and a resource for further studies on antimicrobial resistance and virulence mechanisms in this strain.