Provided is a conductive polymer composite material including an intrinsically conductive polymer, a cellulose nanofiber, and a polyol, wherein the surface of the cellulose nanofiber contains a carboxylic group. In one embodiment, based on 100 parts by weight of the intrinsically conductive polymer, the content of the cellulose nanofiber is 1 to 100 parts by weight, and the content of the polyol is 10 to 3,000 parts by weight. A capacitor including the conductive polymer composite material is also provided.