Spherical Nb2O5 was synthesized by hydrothermal method, and further calcined into porous spherical Nb2O5. Two activated samples were used as cathode materials for pseudo-capacitors. The morphology and structure of two samples were studied by X-ray and scanning electron microscopy. Both samples were of spherical structure, and porous spherical Nb2O5 had abundant ion channels and mesoporous which made it be equipped with excellent electrochemical properties. Two activated samples were used as cathode materials for pseudo-capacitors, the electrochemical properties were compared. The results showed that the porous spherical Nb2O5 was better than spherical Nb2O5, and porous spherical Nb2O5 displayed high specific capacitance of 351 F/g at the current density of 0.5 A/g, good rate capacity of 225 F/g at the high current density of 5.0 A/g and impressive capacitance retention of 92% after 3 000 cycles at the current density of 2.0 A/g. This Nb2O5 nanomaterial proved to have certain reference and application value.