In this study, RGDS and KRSR peptides were immobilized onto electrospun silk fibroin (SF) nanofibrous mats by imide bond formation, and the cell affinities were evaluated as an immobilized SF scaffold. The MTT assay showed that cell adhesion and spreading of normal human dermal fibroblast (NHDF) occurs on SF nanofibrous mat with immobilized RGDS peptide in the early culture time (within 2-4 h after seeding). On the other hand, the KRSR peptide was more effective on normal human osteoblasts (NHOst). Therefore, the cell adhesion peptides RGDS and KRSR are effective in improving cell adhesion, spreading and proliferation of specific cell types. Moreover, these effects depend on the peptide density. The performance of the SF nanofibrous mats with immobilized peptides may be enhanced as a scaffold for specific uses.