The present invention has an object of providing the carbon fiber (or the nonwoven fabric configured of the aforementioned carbon fiber) of which the surface area, the graphitization degree, and the fiber diameter are large, high, and small, respectively, and yet of which dispersion is small.The method of producing the carbon fiber nonwoven fabric includes a dispersion liquid preparing step of preparing a dispersion liquid containing resin and pitch, an electrospinning step of producing the nonwoven fabric that is comprised of carbon fiber precursors with electrospinning from the aforementioned dispersion liquid, and a modifying step of modifying the carbon fiber precursors of the nonwoven fabric obtained in the aforementioned electrospinning step into the carbon fiber.