To obtain a solid activated carbon having high strength, preventing breakage is use when used as an electrode of an electric double layer capacitor, by adding a specific component to activated carbon powder and/or activated carbon fiber.

This solid activated carbon comprises activated carbon powder and/or activated carbon fiber, a carbide obtained by heat treating the binder component such as a thermosetting resin, etc., and a silicone or silicone compound obtained by heat treating a silane coupling agent. The activated carbon is obtained by mixing its powder and/or fiber and the binder component such as the thermosetting resin, etc., and silane coupling agent, molding the obtained mixture and heat treating under non-oxidizing atmosphere. The addition amount of the silane coupling agent is preferably in a range of 1-150 pts.wt. per 100 pts.wt. of activated carbon powder and/or fiber. The mixing ratio of a solid component consisting of activated carbon powder and/or fiber and binder is set to be 50-95wt.% solid component and 5-50wt.% binder.