The invention relates to a lightweight high-temperature-resistant thermal protection material and a preparation method thereof, belonging to the field of inorganic functional materials. The preparation method, provided by the embodiments of the invention, of the lightweight high-temperature-resistant thermal protection material comprises the steps of carrying out needle puncture on a carbon cloth and net tire gradient interlaced and laminated body to form carbon fiber fabric with density gradient distribution in a thickness direction; forming matrix carbon at fiber overlapping joint parts of the carbon fiber fabric, and forming a protective layer on the surfaces of the internal fibers so as to realize the fabric sizing; adopting a directional densification method to directionally densify a high density area so as to form an integrated material which has a dense surface layer, is internally porous and is connected by an intermediate transitional structure; finally, preparing an oxidation protective coating on the densified surface so as to form an integral lightweight thermal protection and insulation material. The lightweight high-temperature-resistant thermal protection material effectively solves the problem that in the prior art, a thermal protection part needs to be mechanically connected with a thermal insulation part, and can greatly simplify the complexity of a thermal protection system, so that the application scope of the thermal protection material is expanded.