The invention discloses a carbon fiber composite material honeycomb and a preparation method and application thereof. A hole wall material defining honeycomb hole lattices is a carbon fiber composite material laminated combination body, and the carbon fiber composite material honeycomb is prepared by laying and compacting unidirectional carbon fiber prepreg according to a preset laying sequence. The preparation method comprises the steps: firstly, paving prepreg and carrying out cold pressing to obtain a hole wall laminated combined body blank, then repeatedly paving the laminated combined body blank by utilizing a mold until the width of a honeycomb to be prepared is reached, finally, simultaneously realizing shape maintenance curing and node gluing curing of the laminated combined body, and thus realizing the preparation of the light high-strength high-rigidity carbon fiber composite material honeycomb. The requirements of weight and comprehensive mechanical property indexes (comprising plane stretching, plane compression, plane shearing performance, long beam bending performance and the like) of the honeycomb are met.