Faceted crystals with different exposed planes have attracted intensive investigations for applications. Herein, we report a facile hydrothermal and thermal decomposition process which is successfully developed to grow 3D NiCo2O4 micro-spheres constructed with radial chain-like NiCo2O4 nanowires with different exposed crystal planes. When applied as electrode materials for supercapacitors, chain-like NiCo2O4 nanowires exhibit excellent electrochemical performances in supercapacitors with high specific capacitance (1284 F g−1 at 2 A g−1), good rate capability, and excellent cycling stability (only 2.5% loss after 3000 cycles). In situ electrical properties clearly illustrated that the chain-like nanowires with different exposed crystal planes exhibit excellent electronic conductivity, which shows that the electronic conductivity plays an essential role for electrode materials in supercapacitors. So, high electronic conductivity chain-like NiCo2O4 nanowires with different exposed crystal planes can form a competitive electrode material for next generation supercapacitors.