[Problem] To provide an apparatus for denaturing double strand nucleic acids to single strand nucleic acids, and a method for denaturing double strand nucleic acids to single strand nucleic acids, which may become an alternative means to the thermal denaturation.[Solution] A nucleic acid denaturation apparatus 100 according to the present invention is provided with a vibration generation part 10 for generating vibration to be given to a nucleic acid solution containing double strand nucleic acids, which gives the vibration that occurs in the vibration generation part to the nucleic acid solution, thereby denaturing the double strand nucleic acids in the nucleic acid solution to single strand nucleic acids.