Cheng can be a transcription of one of several Chinese surnames. Since the syllable Cheng represents different sounds in Hanyu pinyin and the Wade–Giles systems of Chinese romanization, some ambiguity will exist as to which sound is represented by the letters "Cheng" if the romanisation and tone is not known. Also within each system of romanisation, each syllable can represent one of several different characters, as with any Chinese syllable.
In the pinyin system of romanization (usually used in China), the most common surnames romanized as Cheng are 程 and 成. In 2019 程 was the 44th most common surname in mainland China.
In names romanized in Wade–Giles (usually used in Taiwan), Cheng is most commonly a transcription of 鄭/郑 (pinyin Zhèng). Cheng can also be the Cantonese version of Zheng (鄭) and Jing (井), non-standard romanization of Cen (岑), and Teochew or Hokkien pronunciation of Zhong (鍾) and Zhuang (莊).
Further confusion arises because Wade–Giles often appears without the required apostrophes (which indicates aspiration), and thus some Wade–Giles names which are properly romanized Ch'eng (such as 程 pinyin Chéng) will appear as Cheng.
Origins
There are a number of accounts of the origin of the same 成 (Chéng) surname. It was the name of fiefdom Cheng (郕) in Henan belong to Shu Wu, a son of King Wen of Zhou. His descendants adopted the name Cheng, simplifying it to 成 by dropping the radical. Similarly, descendants of Ji Zai, who was granted another fief of the same name in Shandong by King Wu of Zhou, also simplified the name and adopted it as their surname. The name may also be derived from a fief of the name Cheng 成 in the state of Lu. Descendants of a Cheng Hu (成虎), son of the ruler of Chu Ruo'ao, also adopted Cheng as their surname. Others are descendants of Tu Ge invaders and other tribes in China.