Modern geological research on the Korean Peninsula was conducted by Japanese geologists during the Japanese colonial period. These researchers mapped the peninsula’s geological structure, identifying and naming various strata and rock units. However, in this process, Japanese scholars often ignored local names in favor of Japanese pronunciations. Furthermore, they grouped the Cambrian and the Ordovician strata – despite their distinct depositional times – into a single chronostratigraphic unit, “System.” This paper examines the transition of Early Paleozoic nomenclature from the "Chosen System" to the "Joseon Supergroup" as led by Korean geologists between the mid-1950s and early 1980s. This was a process of changing English regional names that had been pronounced in the Japanese way into Korean regional names, and at the same time, it was a process of systematizing and universalizing the unit called ‘System’ in accordance with the international standard of ‘Supergroup.’ This paper shows that the renaming and reclassifying the Chosen System into the internationally standardized Joseon Supergroup was a unique process that simultaneously restored locality and universality.