Abstract: Using chitosan as raw materials, O-carboxymethyl chitosan was prepared and used to treat cotton fabric surface in alkaline conditions, with silicone coupling agent KH560 as crosslinking agent. The infrared spectroscopy, thermal analysis and SEM were used to characterize the structure and morphology of the modified cotton. The effect of the different process conditions on the physical and mechanical properties and dyeing properties of cotton fabric were studied. The results showed that the strength of modified cotton increases, and wrinkle resistance has been improved but the whiteness decreased.Modified cotton could obtain a higher K/S values at 70 ℃with methylene blue, and the adsorption kinetics of methylene blue dye fitted the quasi，first-order kinetic model.

Key words: carboxymethyl chitosan; silane coupling agent; cotton fabric; dyeing