The invention discloses a preparation method of a carbon nanotube composite material, and belongs to the field of electrode material preparation, and the preparation method comprises the following steps: taking a nickel-based Prussian blue substance synthesized by a normal temperature precipitation method as a precursor, and then sequentially introducing nitrogen, nitrogen and hydrogen, nitrogen, nitrogen and propylene to carry out heat treatment on the precursor. The Prussian blue analogue precursor integrates a catalyst, a nitrogen source and part of a carbon source, and compared with a traditional catalyst for a carbon nanotube, the precursor has the advantages that the particle size is uniform, and the consumption of carbon source gas can be reduced; the transition metal can improve the specific capacitance of the carbon nano tube, the nitrogen doping can improve the conductivity of the carbon nano tube, and the carbon layer can play a structural protection role on the transition metal nano particles packaged in the carbon layer, so that the cycle life of the composite material is prolonged.