Carboxymethylated cellulose nanofibers in which the cellulose type I crystallinity is 60% or higher, the aspect ratio is 350 or lower, and the transmittance of light having a wavelength of 660 nm when the carboxymethylated cellulose nanofibers are made into an aqueous dispersion having a solids fraction of 1% (w/v) is 60% or higher.