A hierarchical MnMoO4/CoMoO4 heterostructured nanowire was synthesized using a simple refluxing method under mild conditions. The nanowires exhibit a high specific capacitance of 187.1 F g−1 at a current density of 1 A g−1 and good reversibility with a cycling efficiency of 98% after 1,000 cycles. These results demonstrate that constructing 3D hierarchical heterostructures can improve electrochemical properties. The 'oriented attachment' and 'self-assembly' crystal growth mechanisms were proposed to explain the formation of the heterostructures. The heterostructured nanowires were used to fabricate asymmetric supercapacitors, which showed excellent performance in terms of specific capacitance, energy density, and cycling stability. The hierarchical structure provides a large surface area, which enhances the electrochemical performance by increasing the number of active sites and improving the accessibility of inner active sites. The heterostructures also facilitate the redox reactions and allow for efficient charge storage due to the enhanced ion transport and the presence of multiple redox couples. The study highlights the potential of hierarchical heterostructured nanomaterials in energy storage applications.A hierarchical MnMoO4/CoMoO4 heterostructured nanowire was synthesized using a simple refluxing method under mild conditions. The nanowires exhibit a high specific capacitance of 187.1 F g−1 at a current density of 1 A g−1 and good reversibility with a cycling efficiency of 98% after 1,000 cycles. These results demonstrate that constructing 3D hierarchical heterostructures can improve electrochemical properties. The 'oriented attachment' and 'self-assembly' crystal growth mechanisms were proposed to explain the formation of the heterostructures. The heterostructured nanowires were used to fabricate asymmetric supercapacitors, which showed excellent performance in terms of specific capacitance, energy density, and cycling stability. The hierarchical structure provides a large surface area, which enhances the electrochemical performance by increasing the number of active sites and improving the accessibility of inner active sites. The heterostructures also facilitate the redox reactions and allow for efficient charge storage due to the enhanced ion transport and the presence of multiple redox couples. The study highlights the potential of hierarchical heterostructured nanomaterials in energy storage applications.