Abstract: Lithium-ion batteries are widely used in portable electronics, but their application in grid-scale energy storage is limited due to lithium’s high cost and resource constraints. As a more affordable alternative, sodium-ion batteries (SIBs) offer the promise of large-scale deployment. Among various cathode materials, O3-type NaNi_0.4Fe_0.2Mn_0.4O₂ (NFM424) demonstrates high capacity and ease of synthesis, yet suffers from structural degradation and sluggish Na⁺ kinetics caused by large ionic radius and strong electrostatic interactions. To overcome these issues, a configuration strategy combined with TiO₂ and Co₃O₄ was introduced to improve structural and electrochemical stability. The resulting NaNi_0.4Fe_0.2Mn_0.3Co_0.05Ti_0.05O₂ (NFMCT) cathode mitigated Na⁺/vacancy ordering while enhancing phase integrity and diffusion pathways. Synthesized via high-temperature solid-state reaction, NFMCT maintained 93.7 mAh·g^–1 after 550 cycles at 1 C, with superior rate capabilities at 2 C and 5 C. These findings deepen the understanding of configuration strategy by using multi-element oxide and highlight a practical strategy for designing high-performance SIB cathodes.