Traditional Resistive Random Access Memory (RRAM) is a metal-insulator-metal (MIM) structure, in which metal oxide is usually used as an insulator. The charge transport mechanism of traditional RRAM is attributed to a metallic filament inside the RRAM. In this paper, we demonstrated a novel RRAM device with no metal inside. The N + -Si/SiO x /P + -Si combination forms a N + IP + diode structure that is different from traditional MIM RRAM. A large high-resistance/low-resistance window of 1.9 × 10 4 was measured at room temperature. A favorable retention memory window of 1.2 × 10 3 was attained for 10 4 s at 85 °C. The charge transport mechanism of virgin, high- and low-resistance states can be well modeled by the single Shklovskii-Efros percolation mechanism rather than the charge transport in metallic filament. X-ray photoelectron spectroscopy demonstrated that the value of x in SiO x was 0.62, which provided sufficient oxygen vacancies for set/reset RRAM functions.