Highly reproducible bipolar resistance switching was demonstrated in a composite material of W-implanted silicon dioxide. Because of its excellent dielectric properties, SiO2 was selected as the sole active material for fabricating the resistance switching devices. The device employed a metal-insulator-semiconductor structure, showing an excellent resistance switching performance (the ON/OFF ratio is close to ∼106). In addition, this sandwich structure device shows a forming-free resistance switching behavior. The overall device performance of the SiO2-based memristor has the potential to open up a new avenue to a large-scale high-performance resistive random access memory, which could significantly impact their existing applications.