A fine carbon fiber having linearity, each fiber filament of the carbon fiber having a bending angle of 30° or less with respect to the longitudinal direction of the fiber filament, and including a hollow space extending along its axis, and having an outer diameter of 1 to 1,000 nm, an aspect ratio of 5 to 1,000, and a BET specific surface area of 2 to 2,000 m2/g, wherein the average interlayer distance (d002) of the carbon fiber at a (002) plane is 0.345 nm or less as measured by means of X-ray diffractometry, and the ratio of the peak height (Id) of the band at 1,341 to 1,349 cm−1 in a Raman scattering spectrum of the carbon fiber to that of the peak height (Ig) of the band at 1,570 to 1,578 cm−1 in the spectrum (Id/Ig) is 0.1 to 2. The fiber exhibits excellent dispersibility in a matrix.