According to the present invention, a method of purifying ubiquinone-10, which includes separating and removing a substance structurally similar to ubiquinone-10 contained in a starting material solution containing ubiquinone-10 by the use of a porous crosslinked acrylic polymer, more preferably, a method of purifying ubiquinone-10 by separating and removing a substance structurally similar to ubiquinone-10 contained in a starting material solution, which includes feeding a starting material solution containing ubiquinone-10 in a simulated moving bed chromatography apparatus wherein a solution can circulate in one direction in a packed-bed wherein a porous crosslinked acrylic polymer is packed, and flowing an eluent in the packed-bed in one direction, is provided.