The global proteomic of Kcr in Aeromonas hydrophila was mapped, and 4424 Kcr sites on 1248 proteins were identified using LC-MS/MS. Gene ontology analysis indicated that in the category of 'biological processes', Kcr proteins are primarily enriched in cellular and primary metabolic processes, response to stress, macromolecule biosynthetic processes, and transmembrane transport. The enrichment of KEGG-annotated Kcr proteins were also evaluated, which showed that the proteins are involved in diverse metabolic pathways, including pentose phosphate pathway, citrate-TCA cycle, methane metabolism.