It is still a critical challenge to increase the flexibility of regenerated fibroin materials in dry and near dry states. In this study, a novel biocompatible and water-stable film composed of fibroin and collagen was successfully prepared from aqueous fibroin solution without methanol treatment. The result of contact angle measurement indicates that hydrophilicity is evidently increased when collagen was added to fibroin film. The elongation at break in wet state is also increased because of the blending of collagen, which implied the improvement of flexibility. More importantly, the blend films containing 20% collagen become flexible when placed at above 65% humidity in atmosphere. It means that the blend films could be fabricated to different conformations easily through adjusting humidity in atmosphere. HepG2 cells were cultured on fibroin and fibroin/collagen films to investigate the cytocompatibility of these films. Scanning electron microscopy and MTT analysis demonstrated that the adding of collagen evidently improved HepG2 proliferation in over 10 days culture. The excellent cytocompatibility, the flexibility in the near dry state as well as the green preparation process of fibroin/collagen blend films make them become the promising biomaterials for different medical applications. (C) 2008 Wiley Periodicals, Inc.