Ti3C2Tx shows potential as an electrode material of supercapacitors due to its unique layered structures for ion diffusion as well as excellent chemical/physical properties. However, the layer stacking and the insufficient conductivity due to the terminated surface groups have limited this application essentially. In the present study, a three-dimensional B3+ ion-intercalated Ti3C2Tx network (B-Ti3C2Tx) was combined with hollow carbon nanospheres (HCNS), which improved the electric transport performance of Ti3C2Tx by reducing the surface functional groups and hindering the restacking of Ti3C2Tx nanosheets effectively. Thus, a new set of 3D hierarchical B-Ti3C2Tx/HCNS composite materials was obtained here with a superior electrochemical performance higher than that of single Ti3C2Tx in the present study, and many other reported Ti3C2Tx-containing materials in literature. In addition, an excellent electrochemical cycling stability with above 91% retention over 3000 cycles was also obtained for this new hybrid material. This work provides a new direction to promote the Ti3C2Tx-based materials for high-performance supercapacitors.