The Nationalist government of China adopted Gwoyeu Romatzyh as the official system for the romanization of Mandarin Chinese.

The Nationalist government, officially the National Government of the Republic of China, refers to the government of the Republic of China from 1 July 1925 to 20 May 1948, led by the nationalist Kuomintang (KMT) party.

Gwoyeu Romatzyh is a system for writing Standard Chinese using the Latin alphabet. It was primarily conceived by Yuen Ren Chao (1892–1982), who led a group of linguists on the National Languages Committee in refining the system between 1925 and 1926. In September 1928, it was adopted by the Republic of China as the national romanization system for Standard Chinese. GR indicates the four tones of Standard Chinese by varying the spelling of syllables, a method originally proposed by team member Lin Yutang (1895–1976). Distinct sets of spellings are assigned to syllables in GR according to particular rules. This differs from approaches used by other systems to denote tones, like the numerals used by the earlier Wade–Giles system, or the diacritics used by the later Hanyu Pinyin system.

Romanization of Chinese is the use of the Latin alphabet to transliterate Chinese. Chinese uses a logographic script and its characters do not represent phonemes directly. There have been many systems using Roman characters to represent Chinese throughout history. Linguist Daniel Kane wrote, "It used to be said that sinologists had to be like musicians, who might compose in one key and readily transcribe into other keys." The dominant international standard for Standard Mandarin since about 1982 has been Hanyu Pinyin, invented by a group of Chinese linguists, including Zhou Youguang, in the 1950s. Other well-known systems include Wade–Giles and Yale romanization.