A two-dimensional (2D) SnNb2O6/amino-functionalized graphene (En-RGO) nanocomposite with a representative 2D-2D architecture has been constructed by an easy self-assembly approach and firstly investigated as anode materials for secondary sodium-ion batteries.The SnNb2O6 nanosheets are evenly anchored with the aminofunctionalized graphene through electrostatic attractive interplay between the negatively charged SnNb2O6 and positively charged En-RGO after modification.As a result,a remarkable reversible capacity of 300 mAh·g-1 was obtained at 50 mA·g-1,and significantly,the En-RGO electrode could also deliver ultra-long calendar life up to 1900 cycles with a high reversible capacity of 200 mAh·g-1 at current of 500 mA·g-1.Such excellent electrochemical characteristics can be mainly ascribed to its fast pseudo-capacitive energy storage mechanism,and the capacitive contribution can even reach up to 90％ at 1.2 mV·s-1.