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In this study, the aqueous re-dispersibility of starch nanocrystal (SNC) powder was significantly improved by sodium hypochlorite (NaClO) oxidation, with more than 2% (w/w) active chlorine. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses verified the oxidation process of SNC. The oxidation degree (carboxyl groups content) increased from 0.41% to 0.581% (w/w) while the applied active chlorine increased from 1% to 4% (w/w). X-ray diffraction showed that NaClO oxidation induced minor destruction to SNC when the applied active chlorine exceeded 2%, and the relative crystallinity decreased from 45.6% to 42.8%. Due to the introduction of carboxyl groups, the zeta potential of oxidized SNC (OSNC, under 2% active chlorine level) suspension (re-dispersed from oven-dried OSNC powder) reached to −23 mV. Consequently, a high degree of individualized SNC with the particle size of 20 nm was obtained and the suspension maintained the stability for at least 20 days. [ABSTRACT FROM AUTHOR]