Sb nanoparticles encapsulated in 3D reticular carbon network (denoted Sb@3D RCN) film are prepared by the electrostatic spray deposition technique followed by a heat treatment. When used as a binder-free anode for a Na-ion battery, it shows excellent long-life cyclability. The unique reticular, porous, and core-shell structure of Sb@3D RCN contributes significantly to the excellent sodium storage performance.