Microbes, such as bacteria and fungi that attach or enter into human bodies through either wounds or natural openings, and disease-spreading insects such as mosquitoes, usually are present in our living environment. These can be hazardous to our health if the human environment, especially those comprising of textile materials, is kept unhygienic. With the current public awareness of environmental sanitation for good health, there has been an increasing demand for disinfected, hygienic, clean, easy-care, comfortable, and protective cotton textiles. These have been studied through the incorporation of synthetic and natural agents onto cotton materials, to provide advanced biological functions such as antimicrobial activity, wound healing, insecticidal potential. This chapter, therefore, reports the current state-of-art for modification of cotton fabrics for advanced biological applications. It also highlights the developments in the biocidal agents, incorporation mechanisms and imparting techniques, the treated bugs, quality, and effectiveness of the obtained products. Finally, the chapter is wrapped up with concluding remarks, including research gaps and future opportunities.