The invention discloses a process for preparing nuclear-grade hafnium oxide and zirconium oxide through solvent extractive separation of zirconium and hafnium. The process comprises the following steps: (1) mixing tributyl phosphate or tributyl phosphate and ionic liquid, which serve as extractants, and kerosene, which serves as a diluent, so as to prepare an organic phase; and then, mixing the organic phase with nitric acid, and carrying out countercurrent acidification in a centrifugal extractor; (2) adding zirconium oxychloride, which serves as a raw material, into deionized water, carryingout dissolving, and then, adding hydrochloric acid and nitric acid into the solution, so as to prepare a feed solution containing zirconium and hafnium; (3) carrying out countercurrent extraction onthe acidified organic phase and the feed solution containing zirconium and hafnium, prepared in the step (2), in a centrifugal extractor; (4) carrying out back-extraction on a zirconium-containing organic phase with water, then, carrying out hydrolysis, and carrying out calcination, so as to obtain nuclear-grade zirconium oxide; and (5) enriching hafnium-containing raffinate with P204, then, carrying out back-extraction, carrying out hydrolysis, and carrying out calcination, so as to obtain nuclear-grade hafnium oxide. According to the process, the problems, i.e., complicated process, much waste liquid and environmental pollution in the prior art are solved, and the production efficiency is increased.