Abstract: For exploiting the advanced functional fiber and new cellulose-based materials,a new cotton fiber modified with collagen protein was prepared through limited selective oxidation of cotton thread by sodium periodate,followed by reacting with the solution of collagen protein.Through analyzing the micro-morphology and the aggregation structure of cotton fiber treated with collagen protein,the changes in the micro-structure of cotton fiber coated with collagen were studied.The analysis suggested that the imine structure bonds were formed between collagen molecule and oxidized cotton fiber,and the treated fiber exhibited little change in crystallinity and marked enhancement in thermal stability.