PROBLEM TO BE SOLVED: To provide magnetized nucleic acid and magnetized nucleotides, and a synthesizing method and a utilization method thereof.SOLUTION: There are provided magnetized nucleic acid and magnetized nucleotides shown by the following formula, and a synthesizing method and a utilization method thereof. In the formula, B denotes adenine, guanine, cytosine, uracil and thymine, Y denotes hydrogen atom or hydroxyl group, M denotes trivalent Fe, divalent Fe, divalent Co, divalent Mn, trivalent Dy and trivalent Nd, X denotes halogen atom such as fluorine atom, chlorine atom, bromine atom and iodine atom. Further, a denotes an integer 3 or 4, and n denotes an integer from 21 to 300.