The present invention provides a hydrocarbon material with a high ion adsorption ability (specific capacitance) per unit volume of the electrode obtained by heating a starting material mainly composed of polysaccharides, which are easy to obtain and inexpensive. More specifically, the hydrocarbon material can be obtained by heating a polysaccharide-based raw material together with a heat reaction auxiliary under an inert gas atmosphere, and has the following properties: (a) the hydrogen/carbon ratio (atomic ratio) is within the range of 0.05 to 0.5; (b) the specific surface area determined by the BET method is in the range of 600 to 2000 m.sup.2g; (c) the mesopore capacitance determined by the BJH method is in the range of 0.02 to 1.2 ml/g; (d) the total pore volume measured by the MP method is in the range of 0.3 to 1.25 ml/g; and (e) the bulk density of an electrode obtained using the hydrocarbon material is 0.60 g/ml or higher.