|Centuries:||3rd century – 4th century – 5th century|
|Decades:||300s 310s 320s – 330s – 340s 350s 360s|
|Years:||330 331 332 – 333 – 334 335 336|
|333 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1086|
|Chinese calendar||壬辰年 (Water Dragon)
3029 or 2969
— to —
癸巳年 (Water Snake)
3030 or 2970
|- Vikram Samvat||389–390|
|- Shaka Samvat||255–256|
|- Kali Yuga||3434–3435|
|Iranian calendar||289 BP – 288 BP|
|Islamic calendar||298 BH – 297 BH|
|Minguo calendar||1579 before ROC
|Seleucid era||644/645 AG|
|Thai solar calendar||875–876|
Year 333 (CCCXXXIII) was a common year starting on Monday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Dalmatius and Zenophilus (or, less frequently, year 1086 Ab urbe condita). The denomination 333 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
- Flavius Dalmatius and Domitius Zenofilus are appointed consuls.
- Emperor Constantine the Great pulls Roman troops out of Britain and abandons work on Hadrian's Wall.
- Calocaerus revolts against Constantine I and proclaims himself emperor. Flavius Dalmatius, responsible for the security of the eastern frontier, is sent to Cyprus to suppress the rebellion.
- December 25 – Constantine I elevates his youngest son Constans to the rank of Caesar at Constantinople.
- Shi Hong succeeds his father Shi Le as Emperor of the Later Zhao Empire, in the Period of the Sixteen Kingdoms.
- Empress Liu
- Murong Hui, Xianbei chief and Duke Xiang of Liaodong (b. 269)
- Shi Le, founder and emperor of the Chinese Jie state (b. 274)