To provide a nanocarbon dispersant satisfying both of dispersion stability of nanocarbon in a solvent and high electric conductivity of nanocarbon after being formed into aggregate, and to provide a nanocarbon fluid dispersion obtained using the nanocarbon dispersant, a method for manufacturing a nanocarbon thin film which can manufacture a nanocarbon thin film by a simple operation and is excellent in productivity, and a nanocarbon thin film obtained by the method.

The nanocarbon dispersant has a bulky hemiacetal ester structure as a repeating unit. The fluid nanocarbon dispersion is obtained using the same. The method for manufacturing a nanocarbon thin film uses these. The nanocarbon thin film excellent in electric conductivity and optical transparency is obtained by the method.