Chitosan nanoparticles were prepared as green antibacterial finishing material and enhance antimicrobial activity of cellulose-based fabrics such as cotton and viscose. Two new bifunctional dye Bis (monochlorotriazine) (MCT) and hetero bifunctional (SES/MCT) reactive dyes have been prepared in previous work. Dimedone moiety (5,5- Dimethylcyclohexane-1,3-dione) and applied in cellulose-based fabrics with various chitosan nanoparticles concentrations imparting them antimicrobial activity. In this work the effect of chitosan nanoparticles on dye ability of cellulose-based fabrics were studied from evaluation of the colour strength expressed in K/S values of the dyed fabrics at different concentration of chitosan nanoparticles and the two synthesized used dyes. Results showed that chitosan nanoparticles treated cellulose-based fabrics have higher affinity towards dyeing than untreated cellulose-based fabrics. Also, the antimicrobial properties of the treated fabrics were higher than that of untreated fabrics and give higher exhaustion without using any salts and alkalinity. So, chitosan nanoparticles exhibit cellulose based fabrics high antimicrobial and having dyeing affinity than untreated one. Also, treated dyed fabrics showed very good to excellent fastness properties.