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 c. 1280 AD.
[1] Ong (or Онгь in Russian language-based records) is also an Estonian surname, possibly derived from õng, meaning "fishing rod/hook".
Under the Pe̍h-ōe-jī romanization system, 王 but not the other names includes a circumflex over its vowel: Ông.
In Singapore, Ong is the fifth-most-common surname among Singaporean residents.