The nanostructured silicon surface has been studied using the scanning tunnel microscopy and spectroscopy in air. The local density of electron states was defined as normalized differential tunnel conductivity (dI/dU)(I/U). The surface morphology has been found to be characterized by the presence of a homogeneous nanostructure on the initial substrate microrelief. For the first time it has been shown that the spectrum of electron states changes considerably during the growth of a nanostructured silicon film.