Romanisation of the Wenzhou dialect of Wu Chinese, part of the greater Ōu (simplified Chinese: 瓯; traditional Chinese: 甌) grouping of Wu dialects centred on the city, refers to the use of the Latin alphabet to represent the sounds of the dialect group.
The first instance of Wenzhounese romanisation begins with the language documentation efforts of Christian missionaries who translated the Bible into many varieties of Chinese in both Chinese characters and in phonetic romanisation systems based largely on the Wade-Giles system. The first romanised form of Wenzhounese can be seen in an 1892 Gospel of Matthew translation.
In 2004, father-and-son team Shen Kecheng (Chinese: 沈克成; pinyin: Shěn Kèchéng) and Shen Jia (Chinese: 沈迦; pinyin: Shěn Jiā) published the work Wenzhouhua (simplified Chinese: 温州话; traditional Chinese: 溫州話; pinyin: Wēnzhōuhuà), which outlines a systematic method for romanising each initial and rhyme of the dialect. Its primary orthographic innovation is its means of expressing the three-way distinction of Wu stops in an orthography that distinguishes only between voiced and unvoiced stops.
The Wade-Giles-based systems deal with this as k, k', and g to represent /k/, /kʰ/, and /ɡ/. Since voiced obstruents no longer exist in Standard Chinese, pinyin deals with /k/ and /kʰ/ as g and k respectively. The Shens use the same basic method and transcribe voiced stops by duplicating the voiced series of letters so /ɡ/ is gg in the system. Likewise, /ɦ/ is transcribed as hh.
They adopt other pinyin conventions, such as x for what is normally transcribed in Chinese usage of the IPA as /ɕ/ and c for /tsʰ/. Vowels are transcribed with a number of digraphs, but few are innovations. The influence of Chinese IMEs is seen in their system as well since v denotes /y/ and ov denotes /œy/. Another way that it diverges from pinyin is in Wenzhounese's unrounded alveolar apical vowel /ɨ/, which is written as ii, since, unlike Mandarin, apical vowels are not in complementary distribution with /i/ in Wenzhounese.