Oudong (Khmer: ឧដុង្គ; also romanized as Udong or Odong) is a former town of the post-Angkorian period (1618–1863) situated in present-day Phsar Daek Commune, Ponhea Lueu District, Kandal Province, Cambodia.

A monumental royal necropolis of sovereigns of several centuries is scattered on top of the prominent bisected mountain, which runs from the southeast to the northeast.

Under the reign of King Ang Duong (1841–1850), he constructed canals, terraces, bridges and erected hundreds of pagodas in this region.

Henri Mouhot: "Travels in the Central Parts of Indo-China" 1864: "Udong, the present capital of Cambodia, is situated north-east of Komput, and is four miles and a half from that arm of the Mekon which forms the great lake...Every moment I met mandarins, either borne in litters or on foot, followed by a crowd of slaves carrying various articles; some, yellow or scarlet parasols, more or less large according to the rank of the person; others, boxes with betel.

On this side were numerous processions to the pagoda, marching to the sound of music; there, again, was a band of ecclesiastics in single file, seeking alms, draped in their yellow cloaks, and with the holy vessels on their backs....The entire population numbers about 12,000 souls.