Rational design and synthesis of high performance active materials is one of the most challenging tasks in supercapacitors. Herein, a new three-dimensional (3D) reduced grapheme oxide (RGO)/carbon nanospheres (CNS)/polyaniline (PANI) ternary nanocomposites were prepared facilely and applied as supercapacitor electrode materials. The as-prepared RGO/CNS/PANI ternary nanocomposites were characterized by field-emission scanning electron microscopy (FESEM), Fourier transform infrared (FT-IR) spectra and X-ray powder diffraction (XRD), respectively. An enhanced specific capacitance was demonstrated compared with other binary nano composites RGO/PANI, RGO/CNS and pure RGO or PANT. The RGO/CNS/PANI exhibited a high specific capacitance of 583 F g(-1) at a current density of 1 A g(-1) and excellent cyclic stability with 86% of its initial capacitance at a large current density of 10 A g(-1) after 1000 charge/discharge cycles. In addition, high rate capability (72% capacity retention from 1 to 10 A g(-1)) was obtained due to the synergistic effects of RGO/CNS and PANI. The results indicated that the ternary nanocomposites of RGO/CNS/PANI could be a promising material for supercapacitor electrodes.