Nitrogen-doped carbon microspheres (NCS) were synthesized via a green and convenient high-temperature pyrolysis of polydopamine. The nitrogen doping content and configuration were precisely adjusted by controlling the pyrolysis temperature. Leveraging the unique spherical morphology and abundant pyridinic-N and pyrrolic-N dopants, the resulting NCS, post-treated at 1000°C, showcases superior electrochemical performance. This includes an outstanding initial Coulombic efficiency (ICE) of 73.4%, remarkable reversible capacity of 386.6 mAh g⁻¹, impressive rate capability reaching 180.1 mAh g⁻¹ at 10 A g⁻¹, and unmatched cycling durability with 75.3% capacity retention after 1500 cycles. The substantial electrostatic repulsion facilitated by densely distributed pyrrolic-N atoms effectively expands the carbon interlayer spacing, ensuring efficient and reversible sodium ion intercalation and deintercalation. The abundant pyrrolic-N and pyridinic-N doping significantly augment surface defect density, facilitating rapid electron/ion transport. Furthermore, the low surface area characteristic of the spherical morphology mitigates irreversible sodium ion consumption during the initial solid electrolyte interface (SEI) formation, guaranteeing a high Coulombic efficiency of the electrode. This study presents a novel avenue for the practical design of hard carbon electrodes.