The invention discloses an MXene/conductive polymer composite aerogel. The MXene/conductive polymer composite aerogel is of an integrated three-dimensional grid structure which is formed by insertinglaminated MXene into a conductive polymer aerogel, wherein the conductive polymer comprises one or more of polyaniline, polypyrrole and polythiophene. The invention further discloses a preparation method of the MXene/conductive polymer composite aerogel. The method is characterized in that the MXene and the conductive polymer are mixed with organic solution and then are rapidly cooled and separated under heat inducing and solvent inducing effects under the inert gas protection; then the vacuum drying is carried out to obtain the MXene/conductive polymer composite aerogel.