This study presents a combined experimental–theoretical approach to understanding and optimizing CrO_x-based self-rectifying memristor (SRM) for neuromorphic computing and provides a promising platform for selector-free, low-power crossbar arrays. By using a stencil-assisted DC sputtering technique, a 16 × 16 crossbar array is fabricated and exhibits reliable analog resistive switching, minimal sneak current (≈150 nA), and an excellent rectification ratio up to 2.56 × 10³, demonstrating excellent scalability and array-level uniformity. Charge–voltage measurements reveal capacitor-coupled behavior, including nonlinear, time-dependent charge accumulation. The memristor supports key synaptic functions such as long-term potentiation/ depression (LTP/LTD) and excitatory postsynaptic current modulation, which is tunable by pulse amplitude and width. First-principles calculations show that the Ti/CrO_x/TiO₂/Cr structure exhibits strong asymmetry in both band alignment and interfacial barrier heights, which is plausible for self-rectifying behavior. Furthermore, the band offset at the CrO_x/TiO₂ interface can be modulated by the presence and migration of oxygen vacancies. This enables dynamic modulation of shallow and deep trap states across the oxide layers. This mechanism facilitates analog and multilevel switching, making the proposed structure highly suitable for future in-memory computing architectures.