McCune–Reischauer romanization () is one of the two most widely used Korean language romanization systems. A modified version of McCune–Reischauer was the official romanization system in South Korea until 2000, when it was replaced by the Revised Romanization of Korean system. A variant of McCune–Reischauer is still used as the official system in North Korea. 

The system was created in 1937 by George M. McCune and Edwin O. Reischauer. With a few exceptions, it attempts not to transliterate Korean hangul but to represent the phonetic pronunciation. McCune–Reischauer is widely used outside Korea. 

Korean has phonologically no distinction between voiced and voiceless consonants, but it phonetically distinguishes them. Aspirated consonants like "p'", "k'", and "t'" are distinguished by apostrophe from unaspirated ones, which may be falsely understood as a separator between syllables (as in → "twich'agi", which consists of the syllables "twi", "ch'a" and "gi"). The apostrophe is also used to mark transcriptions of ("n'g") as opposed to ("ng"): → "chan'gŭm" vs. → "changŭm"). 

Critics of the McCune–Reischauer system claim that casual users of the system omit the breves ( ˘ ) over the "o" for and the "u" for because typing "o" or "u" without the breves is often easier than adding them. That can lead to confusion over whether the "o" being romanized is or or the "u" being Romanized is or . Casual users also often omit the apostrophe that differentiates aspirated consonants (, , , and ) from their unaspirated counterparts (, , , and ), which can also lead to confusion.
In what country is a variant of the original still the official system?
 North Korea. 