Pt/ZnO:Ti/n(+)-Si structures that showed reversible and steady resistive switching behaviors were fabricated by magnetron sputtering. The stability of the devices was improved by Ti doping and the switching mechanism of the resistive switching was theoretically studied under the guidance of the first principles. The influences of different Ti atomic doping concentrations on the crystal structure and resistive switching characteristics were also investigated. The results revealed that the oxygen vacancy appears easily around the Ti ions since the formation energies of oxygen vacancies had the minimum value when it located at the next nearest neighboring to Ti atoms. (C) 2013 Elsevier B.V. All rights reserved.