The present invention relates to a method for preparing metal nanostructures using DNA, and more particularly, to a method for preparing metal nanostructures, in which a self-assembling DNA is used as a frame, and thus the orientation, shape and size of the nanostructures are easily controlled compared to conventional bottom-up methods. Metal nanostructures prepared by the method show excellent localized surface plasmon resonance properties, and thus can be used as fluorescent substances in drug delivery, biomedical imaging, and supersensitive biosensors.