Nanofiber that keep crystallinity are obtained from a cellulose material under light load. The nanofiber are obtained by treating a material containing cellulose with 4% by mass or more and 9% by mass or less of an aqueous alkali metal hydroxide solution to produce alkali cellulose, reacting the alkali cellulose with carbon disulfide to give cellulose xanthate, and defibrating the cellulose xanthate. Then, the xanthate is treated with acid or heat to be regenerated into cellulose nanofiber.

Nanofiber that keep crystallinity are obtained from a cellulose material under light load. The nanofiber are obtained by treating a material containing cellulose with 4% by mass or more and 9% by mass or less of an aqueous alkali metal hydroxide solution to produce alkali cellulose, reacting the alkali cellulose with carbon disulfide to give cellulose xanthate, and defibrating the cellulose xanthate. Then, the xanthate is treated with acid or heat to be regenerated into cellulose nanofiber.

It is an object of the present invention to provide fine fibrous cellulose capable of enhancing transparency and suppressing coloring, when the fine fibrous cellulose are processed into a dispersed solution or a sheet. The present invention relates to fine fibrous cellulose, in which the amount of substituents introduced is less than 0.5 mmol/g and the fiber width is 1 to 10 nm. Moreover, the present invention relates to a dispersed solution and a sheet, each of which comprises fine fibrous cellulose. Furthermore, the present invention relates to a method for producing fine fibrous cellulose, comprising: (A) removing at least a part of substituents from fine fibrous cellulose with a fiber width of 1000 nm or less having the substituents, and (B) performing a uniform dispersion treatment on the resulting fine fibrous cellulose after completion of the (A).