Using citrus peels as raw materials, citrus nanofibers were prepared successfully by the method of the combination of 2,2, 6,6-tetramethylpiperidine-1-oxygen radical (TEMPO) oxidation and high pressure homogenization. Meanwhile, the effect of various molality of NaClO (5mmol/g, 25mmol/g, 50mmol/g) on the aspect ratio, morphology, physicochemical properties of citrus nanofibers were investigated. The results showed that with the increase of NaClO molality, the diameter and length of citrus nanofibers were gradually decreased. When the molality of NaClO was 50mmol/g, the diameter and length reached to the shortest, which were (150.57±24.99)nm and (2.74±0.29)nm, respectively. Results of scanning electron microscopy and FTIR spectra revealed that the lignin and hemicellulose in citrus fibers were hydrolyzed in the reaction of TEMPO oxidation with the increase content of NaClO, resulting in a rougher surface. The spectra of X-ray diffraction and thermogravimetry exhibited that TEMPO oxidation and high pressure homogenization treatment could improve the crystallinity and heat resistance of citrus nanofiber, and the formed cellulose I crystals was not destroyed. The analysis of physical and chemical properties of citrus nanofibers showed that the water holding capacity, oil holding capacity, cholesterol adsorption capacity and glucose adsorption capacity could be effectively improved after the TEMPO oxidation and high pressure homogenization treatment. And the strongest adsorption capacity was achieved when NaClO molality was 50mmol/g. The results showed that nano-sized citrus fiber possessed excellent functional properties, and this paper hoped to provide a scientific basis for the reuse of citrus peel.