|Centuries:||3rd century – 4th century – 5th century|
|Decades:||310s 320s 330s – 340s – 350s 360s 370s|
|Years:||343 344 345 – 346 – 347 348 349|
|346 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1099|
|Bahá'í calendar||−1498 – −1497|
|English Regnal year||N/A|
|Chinese calendar||乙巳年 (Wood Snake)
3042 or 2982
— to —
丙午年 (Fire Horse)
3043 or 2983
|- Vikram Samvat||402–403|
|- Shaka Samvat||268–269|
|- Kali Yuga||3447–3448|
|Igbo calendar||−654 – −653|
|Iranian calendar||276 BP – 275 BP|
|Islamic calendar||285 BH – 283 BH|
|Minguo calendar||1566 before ROC
|Thai solar calendar||889|
|Wikimedia Commons has media related to 346.|
Year 346 (CCCXLVI) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Constantius and Claudius (or, less frequently, year 1099 Ab urbe condita). The denomination 346 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.
- Emperor Constans I uses his influence to secure the return of Athanasius. He is restored as Patriarch of Alexandria, and compile documents relating to his expulsion under the title Apology Against the Arians.
- Macedonius I, Patriarch of Constantinople, is deposed again by Paul I.
- Julius Firmicus Maternus writes De erroribus profanarum religionum.
- The Visigoths are converted to Arianism by Wulfila.