Some bonds on the curved surface (CS) of silicon nanostructures can produce localized electron states in the band gap. Calculated results show that different curvature can form the characteristic electron states for some special bonding on nanosilicon surface, which are related to a series peaks in photoluminescience (PL), such as LN, LO1 and LO2 lines in PL spectra due to SiN, Si=O and SiOSi bonds on the curved surface, respectively. In the same way, SiYb bond on the curved surface of Si nanostructures can manipulate the emission wavelength into the window of optical communication by the CS effect, which is marked as LYb line near 1550 nm in the electroluminescience (EL).