PROBLEM TO BE SOLVED: To provide a method for extending longitudinal relaxation time and transverse relaxation time in nuclear magnetic resonance (NMR), while removing free radicals from hyperpolarized solution. SOLUTION: A method for preparing samples for magnetic resonance measurement by using dissolution dynamic nuclear polarization-based hyperpolarization, includes the step (1.1) to prepare frozen beads of a first kind containing paramagnetic substances in addition to a solute under examination; the step (2.1) to insert the frozen beads into a polarization magnet; the step (3.1) to create a higher polarization state of the nuclei in a magnetic field; the step (4.1) to heat the sample up to room temperature, the step (5.1) to transfer samples into MR magnet; and the step (6.1) to perform MR measurement. Further, additional steps are included, the step (1.2) to prepare frozen beads of a second kind containing a reduction agent, and the step (2.2) to insert the frozen beads of a second kind together with the frozen beads of the first kind into the polarization magnet. ;COPYRIGHT: (C)2011,JPO&INPIT