Analysis of different samples of the Sphinx's rock and the surrounding plateau was carried out using x-ray diffraction analysis (XRD) to determine the nature and source of salt which led to its deterioration. The XRD data demonstrated that halite and gypsum salt are naturally occurring minerals in the limestone mother rock of the Sphinx. The subsoil water and moisture surrounding the Sphinx play an important role in dissolving salts, their migration, and recrystallization at the surface. Stabilization of the existing salts by controlling the effect of water and applying consolidants and water-repellent materials is the best method for conservation of the Sphinx.