•We fabricate hierarchical carbon nanotube/α-Ni(OH)2 nanosheet composite paper.•A facile chemical bath deposition was used.•The composite paper shows good electrochemical performance.Carbon nanotube (CNT)/α-Ni(OH)2 composite paper based on CNT paper was prepared by a facile chemical bath deposition (CBD) method. α-Ni(OH)2 nanosheets were vertically grown on individual CNTs in CNT paper to form hierarchical nanowires. The loading mass of α-Ni(OH)2 in the composite paper could be 66 wt%. Thus the composite paper showed much higher specific surface area than that of pristine CNT paper. This novel structure brings the composite paper an electrochemical capacitance high to 1144 F/g at the current density of 0.5 A/g, and maintains 585 F/g at 10 A/g. This composite paper could be a promising candidate for the electrodes of high-performance supercapacitors.