The present work describes synthesis of copper alginate-cotton cellulose and chitosan attached cotton composite fibers and detailed investigation of antimicrobial action against the model bacteria E.coli. The fibers were prepared by different techniques. The resulting fibers were investigated for their biocidal action against E.coli, by using zone inhibition and colonies counting method. Finally, fibers were reduced with sodium borohydride to yield copper nanoparticles- loaded composite fibers and investigated for biocidal action. It was found that these fibers possessed both, the fair mechanical strength and antibacterial action. The extent of biocidal action was found to depend upon the amount of Cu(II) loaded and concentration of alginate into cotton- cellulose fibers. The fibers showed higher Cu(II) release in physiological fluid as compared to distilled water. Copper alginate-cotton cellulose (CACC) fibers show fair mechanical strength and release copper ions in the presence of physiological fluid and protein solution. These fibers have great potential to be used as dressing materials.