Abstract: The composite poly(N-isopropylacrylamide) hydrogel was prepared by radical polymerization via filling of fibroin fiber. The viscoelasticity, swelling and oscillating swellingdeswelling property of composite hydrogel were investigated. Results show that the incorporation of fibroin fiber can improve the mechanical property, and its equilibrium swelling ratio of composite hydrogel is dependent on both temperature and the content of fibroin fiber. Moreover, there are gaps between the fibroin fiber and hydrogel on hydrogel surface, and they act as the transmission channels which are favorable for the outflow and inflow of water from the interior hydrogel in the course of oscillating swellingdeswelling. Thus, the response rate and oscillating swelling-deswelling property of composite hydrogel are improved.