The development of radiochronometry and its application to nuclear materials are one of intense and important research area in the nuclear forensics field. Age dating techniques are based on the decay pattern of the radioactive nuclides. After the chemical separation of each radionuclide, their radioactive progenies begin to grow into the material. Therefore, the date of the last chemical parent-daughter separation can be calculated by determining accurate amounts of parent and daughter isotopes in the sample, respectively. Uranium age dating methods are based on the accurate determination of a daughter-mother radionuclide pair such as 230Th/234U, 231Pa/235U, 214Bi/234U. In particular, the 230Th/234U chronometer is one of the most straightforward chronometers to measure the production date and certainly the most widely applied since the half-life of 234U is relatively short (2.45×105 years) compared to the other uranium isotopes, 235U and 238U. In this study, we adopted the 230Th/234U radiochronometer and evaluated the age dating of two different uranium reference materials by determining 230Th/234U isotopic ratio using MC-ICP-MS. Additionally, quantitative analysis results of Th isotopes using two different spikes for the Isotope Dilution Mass Spectrometry (IDMS) were compared. As a result, the uranium age dating results were in a good agreement with the certified values of both uranium reference materials: uranium oxide and uranyl nitrate. Also, it was confirmed that the ages of uranium oxide reference material along each quantified Th have shown similar values in an allowable error range.