Rosseta mission will flyby the asteroid 21 Lutetia in July 2010. An intensive observational campaign was organised in order to improve the knowledge of its mineralogical and physical characteristics. Several observational campaign were performed between 2003 and 2006 in the 0.8-3.8 µm spectral interval. The spectroscopic observations were carried out in remote mode from CODAM (Meudon, France) by using the NASA’s 3 meter aperture telescope IRTF, located at Mauna Kea-Hawaii. Spectroscopic results were correlated with the asteroid surface by means of physical ephemerides. The 0.8-2.5 µm spectra revealed no major absorption features. The near-equatorial aspect of 21 Lutetia during the 2006 observational campaign allow to conclude to a clear variation between spectra, and their correlation with the rotational period and the geometric aspect. The shallow 3 µm band, presented in the spectrum on 21 Lutetia, privilege a mineralogy where aqueous alteration could be interpreted in terms of minerals favourable to redox reactions. A chi-square test for the available 0.8-2.5µm spectra of obtained since 2003 was performed by means of a chosen sample of meteorites. In all cases, chondrite composition of meteorites yielded the best fit. These results are interpreted as a consistency with the primitive composition of 21 Lutetia.