Resistive switching memory based on transition metal oxides holds great promise for next-generation nonvolatile memory and neuromorphic computing. However, the instability of resistive switching characteristics and the ambiguity of the underlying mechanism in pristine WO3-based memristors hinder their practical applications. Herein, we demonstrate that yttrium (Y) doping strategies effectively modulates the oxygen vacancy concentration and electronic structure of WO3 film, leading to a transition from interface-dominated to bulk filamentary resistive switching behaviors for the constructed devices. Through comprehensive XPS and XRD analyses, we confirm that Y3+ substitution for W6+ introduces additional oxygen vacancies via charge compensation. The underlying mechanism for this phenomenon is revealed by our first-principles calculations, which show a significant reduction in the formation and migration energies of oxygen vacancies upon Y doping. The W/WO3:Y/Pt memristor exhibits highly uniform switching parameters(CVset 8.02% and CVreset 5.10%), long retention (>104 s), and multilevel storage capability. Moreover, the device emulates synaptic functionalities such as long-term potentiation/depression (LTP/LTD) and enables high-accuracy handwritten digit recognition (92.35%) in a neuromorphic network. This work not only presents a feasible doping strategy for enhancing the performance of WO3-based memristors but also provides valuable guidelines for developing other high-performance metal-oxide memristive systems.