Dysregulation of the expression of ubiquitin - specific protease 7 (USP7) has been associated with tumor progression. However, the biological functions and clinical significance of USP7 in renal fibrosis remain insufficiently explored. In this study, proteomic and phosphoproteomic sequencing were performed on NRK - 49F cells with and without USP7 knockout after TGF - β1 stimulation. The aim was to explore the possible mechanism of action of USP7 in the fibrosis process of renal fibroblasts, so as to confirm that USP7 is a potential therapeutic target for alleviating renal fibrosis, and that inhibiting USP7 may be an effective strategy for treating chronic kidney disease (CKD).