Antimony is being extensively investigated as anode material for sodium ion batteries (SIBs) due to its appropriate sodium insertion potentials, flat charge-discharge plateau and high sodium storage capacity. However, it suffers from unsatisfied cycling stability originated from the huge volume change during cycling. Herein, hollow NiSb spheres confined by three-dimensional interconnected carbon matrix (NiSb⊂3DCM) are prepared by a cross-linking reaction between Ni2+ and alginate and a galvanic replacement reaction. Benefiting from its the hollow, porous structure and mechanical buffer provided by Ni and carbon coating, NiSb⊂3DCM electrode can deliver a stable capacity of 366 mAh g−1 with 94.3% capacity retention rate after 400 cycles operated at 1 A g−1, which is the best cycling performance reported so far for Sb-based alloy anodes.