|Centuries:||3rd century – 4th century – 5th century|
|Decades:||320s 330s 340s – 350s – 360s 370s 380s|
|Years:||350 351 352 – 353 – 354 355 356|
|353 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1106|
|Chinese calendar||壬子年 (Water Rat)
3049 or 2989
— to —
癸丑年 (Water Ox)
3050 or 2990
|- Vikram Samvat||409–410|
|- Shaka Samvat||275–276|
|- Kali Yuga||3454–3455|
|Iranian calendar||269 BP – 268 BP|
|Islamic calendar||277 BH – 276 BH|
|Minguo calendar||1559 before ROC
|Seleucid era||664/665 AG|
|Thai solar calendar||895–896|
Year 353 (CCCLIII) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Magnentius and Decentius (or, less frequently, year 1106 Ab urbe condita). The denomination 353 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.
- Battle of Mons Seleucus: Emperor Constantius II defeats the usurper Magnentius, who commits suicide in Gaul in order to avoid capture. Constantius becomes sole emperor and reunifies the Roman Empire.
- Constantius II sends his official Paulus Catena to Britain to hunt down the opponents supporting Magnentius. Flavius Martinus, vicarius of Britain and supporter of Constantius, opposes the persecutions, he is then accused by Catena of being a traitor. In response, Martinus tries to kill Catena with a sword, he fails and then commits suicide.
- Constantius II assembled a conciliabulum at Arles and condemned Athanasius as Patriarch of Alexandria.
- Wang Xizhi, Chinese calligrapher, produces "Preface to the Poems Composed at the Orchid Pavilion" in running script style. It becomes a model for future calligraphers.
- Flavius Martinus, vicarius of Roman Britain
- August 11 – Magnentius, Roman usurper (b. 303)
- August 18 – Magnus Decentius, brother and Caesar of Magnentius
- Zhang Chonghua, ruler of Former Liang (b. 327)