Structural and electronic properties of the as-grown (011) crystal face and the mechanically polished (001) surface of potassium titanyl phosphate (KTiOPO 4 or KTP) have been investigated by core-level x-ray photoelectron spectroscopy and reflection high-energy electron diffraction (RHEED). With XPS analysis the original element binding energies, Auger parameters for K 2p 3/2 and P 2p core levels, relative element contents and valence band structure have been determined for both crystal cuts. A great depletion of O, K and P in the (011) face with respect to the (001) surface was discovered on comparison of element peak areas. The Ti 2p 3/2 peak areas were virtually the same for both cuts investigated. The relative element contents at the (001) surface were very close to the formal composition of KTiOPO 4 , so it is optimal to use the polished (001) KTP surface cleaned by ion bombardment and the Ti 2p 3/2 core level as standards for determination of the chemical composition of doped crystal surfaces.