This study intends to propose a revision or reform of the actual romanization rule of ‘Korea’ and ‘Corea’. ‘Korea’ as well as ’Corea’ originate from the name of the ancient Kingdom of ‘고려(Goryo)’. Therefore the actual romanized names of ‘Korea’ and ‘Corea’ are the phonetic transcriptions of the ‘Goryo’ dynasty. But in my opinion, these are unacceptable, because both are usually pronounced as three-syllable words: Ko-re-a, Co-re-a. In addition to this problem, they are always committed the error of accent, that is, while the original Korean word of 고려(Goryo) is consisted of two syllables and the accent is given at the first syllable, the two actual romanized form of ‘Korea’ and ‘Corea’, at the second syllable: [ko-ri-a]([k□-ri-□]), [ko-re-a]. Considering that the above mentioned problems are derived from the erroneous hiatus of the diphthong ‘ㅕ(j□)’ of ‘고려(Goryo)’, we can solve this problem by means of the diphthongization of the two final vowels -ea, that is, by converting the precedent vowel ‘e’ into the weak high vowel ‘i’, and consequently forming the diphthong -ia. And finally we get a new revised form ‘Coria’.