Durable and rechargeable antimicrobial cotton was prepared from polycarboxylic acid (PCA)-finished cellulose. Sodium perborate solution was employed as an activating and recharging agent to generate peroxyacid structures from cross-linked PCA moieties existing on the PCA-treated fabrics. The peroxyacid structures on the fabrics, characterized by using FTIR and active oxygen analysis, could demonstrate desired antimicrobial functions against Escherichia coli. The antimicrobial functions on the cellulose can be refreshed by using similar sodium perborate solutions in subsequent procedures. But the refreshable functions on the cotton seem to be limited by the peroxyacid formation process. The mechanisms and conditions of the formation of peroxyacid structures on PCA-cross-linked cellulose are discussed in this paper.