In vitro evolution system established early in the 1990s has enabled us to create a specific peptide aptamer (=binder) against various targets. Recently, the technique has been applied to isolate peptide aptamers against metals and semiconductors. For the purpose of creating artificial proteins that functionalize the surfaces of titanium and carbon nanohorns, we have isolated peptide aptamers, TBP-1 and NHBP-1. TBP-1 binds to the surfaces of titanium and carbon nano-materials, and has been shown to have a target specificity against Ti, Ag, and Si. Mutational studies have revealed that the peptide binds to these materials by electrostatic interaction. TBP-1 also has biomineralization activities for Ag, silica and oxidized titanium formation. Thus, TBP-1 is a bifunctional peptide, i.e.,it is a binder as well as a catalyst. By using these peptide aptamers against inorganic materials, novel hybrid materials have been developing.