The structure of an aluminum oxide/graphene oxide (GO) composite was studied using X-ray photoelectron spectroscopy (XPS). High-energy resolved XPS measurements of Al 2p-core level spectra revealed the formation of Al-O-C bonds, which indicated the occurrence of interfacial reactions between Al2O3 and GO in the process of composite synthesis. An increase in intensity in the near-edge region of XPS valence band (VB) spectrum was observed with increasing GO concentration, indicating possible contribution of the electronic states of carbon. Filling the electronic states on the edge of VB allows to associate GO doping with the loss of dielectric properties of the original Al2O3 compound. Addition of graphene oxide to Al2O3 ceramics changed conductive properties of the composite due to formation of new chemical bonds.