Islamic Cairo is a part of central Cairo noted for its historically important mosques and other Islamic monuments. Islamic Cairo was founded in (969 AD) as the royal enclosure for the Fatimid caliphs. Cairo contains the greatest concentration of Islamic monuments in the world, and its mosques, mausoleums, religious schools and baths were built between the seventh and nineteenth centuries. The air pollution in Cairo is a matter of serious concern. Archaeological buildings in Cairo suffer from different deterioration phenomena for example, black crust formation, chemical alterations, disintegration between surface mineral grains, pitting, cracks, missing parts, erosion, and white stains. Building materials which include limestone and marble in addition to salts and surface black crusts had been studied by polarizing microscope (PM), scanning electron microscope (SEM) and X-ray diffraction (XRD) to identify their components and their deterioration. Study for the effect of  nano titanium dioxide and nano lime on stone samples was carried out. Results of stone samples treatment with nanomaterials were evaluated. Nano titanium dioxide gave a good effect in self-cleaning and nanolime (CaLoSiL IP25) gave the best result in consolidation of limestone and marble samples.