A comparative study of two electrode materials is conducted to demonstrate the effect of the electrode material on the resistive switching (RS) behavior of Ta2O5‐based devices. Compared with a Pt top electrode (TE), application of a TiN TE shows an improved endurance of up to 109 cycles and a highly reliable 4 bit (16 states) operation. Various structural analyses reveal that this distinctive RS performance originates from an oxygen‐deficient layer (TaOx) between the Ta2O5 and TiN TEs. This interfacial layer improves the endurance of the device by acting as an oxygen reservoir that prevents the severe consumption of oxygen during repetitive RS and makes the device compatible with electrical pulse–based operations for stable multibit operation by acting as an appropriate load resistor. The results herein suggest that the optimized interfacial layer is essential for the development of high‐performance RS devices for future nonvolatile memory applications.