|Centuries:||3rd century – 4th century – 5th century|
|Decades:||310s 320s 330s – 340s – 350s 360s 370s|
|Years:||341 342 343 – 344 – 345 346 347|
|344 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1097|
|Chinese calendar||癸卯年 (Water Rabbit)
3040 or 2980
— to —
甲辰年 (Wood Dragon)
3041 or 2981
|- Vikram Samvat||400–401|
|- Shaka Samvat||266–267|
|- Kali Yuga||3445–3446|
|Iranian calendar||278 BP – 277 BP|
|Islamic calendar||287 BH – 286 BH|
|Minguo calendar||1568 before ROC
|Seleucid era||655/656 AG|
|Thai solar calendar||886–887|
Year 344 (CCCXLIV) was a leap year starting on Sunday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Leontius and Bonosus (or, less frequently, year 1097 Ab urbe condita). The denomination 344 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.
- The Eastern Roman Emperor Constantius II campaigns in eastern Mesopotamia against the Sassanid Persians
- Battle of Singara: The Roman army under Constantius wins a close victory at the strongly fortified city of Singara (Mesopotamia). His enemy, King Shapur II is forced to lift the siege and withdraw the Persian army.
- Shapur II besiege for the second time the Roman fortress of Nisibis in eastern Mesopotamia, but is repulsed by forces under the general Lucilianus.
- Jin Mudi, age 1, succeeds his father Jin Kangdi as emperor of China. His mother Empress Dowager Chu, becomes the ruling authority at court and served as regent.
- The making of a detail of Admonitions of the Imperial Instructress to Court Ladies (attributed to Gu Kaizhi and being from the Six Dynasties period) begins (approximate year) and is completed in 406. It is now kept at the British Museum, London.
- Bishop Eustorgius I brings relics of the Three Magi from Constantinople to Milan, according to a 12th century legend.
- Gu Kaizhi, Chinese painter (approximate date)
- Kumārajīva, Buddhist monk and translator (d. 413)
- Mary of Egypt, patron saint (approximate date)
- Wang Xianzhi, Chinese calligrapher (d. 386)
- Zhang Yaoling, ruler of Former Liang (d. 355)
- Biryu of Baekje, king of Baekje (Three Kingdoms of Korea)
- Heliodorus of Bet Zabdai, bishop and martyr
- November 17 – Jin Kangdi, emperor of the Jin Dynasty (b. 322)