The present invention relates to three-dimensional self-assembled nucleic acid nanoparticles, a drug delivery system comprising the same, and a pharmaceutical composition for the prevention or treatment of acute kidney injury, which comprises the same. The three-dimensional self-assembled nucleic acid nanoparticles of the present invention, which have a tetrahedral structure, exhibit an excellent renal-targeting ability, and thus the nanoparticles conjugated with the pharmaceutically active ingredient for p53 exhibit excellent p53 and caspase 3 expression reductions in vitro and in vivo, and can thereby be applied to the prevention or treatment of acute kidney injury.