Ng (pronounced [ŋ̍]; English approximation often /ˈɪŋ/ or /ˈɛŋ/) is a Cantonese and Hakka transliteration of the Chinese surnames 吳/吴 (Pinyin transliteration for Mandarin equivalent: Wú) and 伍 (Mandarin Wǔ) meaning "five". In Hokkien (Taiwanese) and Teochew, Ng corresponds to the surname 黃/黄 (Mandarin Huáng) meaning "yellow"; or to 阮 (Mandarin Ruǎn).
The surname is sometimes romanized as Ang, Eng, Ing and Ong in the United States and Ung in Australia. Ng is sometimes romanized as Woo or Wu even by people of Cantonese origin, such as John Woo. In Vietnam, the corresponding surname is Ngô. In Cambodia, the corresponding surname is Oeng. 吴 / 吳 (Wú) was the 10th most common Chinese surname in 2006 and was the 8th most common in 1990.
Ngô is a Vietnamese surname.
The surname is known as Wu in Chinese (吳 or 吴), Oh in Korean, and Ngov in Khmer.
Ong is a Hokkien romanization of several Chinese surnames: 王 (Wáng in Hanyu Pinyin), 汪 (also Wāng), 黃 (traditional) or 黄 (simplified; Huáng); and 翁 (Weng). Ong or Onge is also a surname of English origin, with earliest known records found in Western Suffolk taxation records from ca. 1280 AD.
Under the POJ romanization system, 王 but not the other names includes a circumflex over its vowel: Ông. However, this is often omitted in practice.
In Singapore, Ong is the fifth-most-common surname among Chinese residents. In the United States, Ong was the 6,682nd most common surname during the 1990 US census and the 4,343rd most common surname during the year 2000 US census.