Year 252 (CCLII) was a leap year starting on Thursday of the Julian calendar. At the time, it was known as the Year of the Consulship of Trebonianus and Volusianus (or, less frequently, year 1005 Ab urbe condita). The denomination 252 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 Barbalissos: King Shapur I defeats the Roman army (some 70,000 men) at Barbalissos in Syria (approximate date).^[1]

• Shapur I puts down the revolt in Khorasan (Iran and Turkmenistan), and rejoins his army.
• Shapur I invades Armenia, and appoints Artavazd VI as the new Armenian king.
• Georgia submits peacefully to Shapur I, and becomes a vassal of the Sassanid Empire.

• Sun Liang succeeds his father Sun Quan, as emperor of the Chinese state of Eastern Wu.

• Pope Cornelius is exiled to Centumcellae, by Emperor Trebonianus Gallus.

• Eusignius of Antioch, Roman general and martyr (d. 362)
• Wang Jun (or Pengzu), Chinese general and warlord (d. 314)
• Wei Huacun, founder of the Shangqing sect of Daoism (d. 334)

• May 21 – Sun Quan, founder of the Eastern Wu state (b. 182)
• Pan (or Pan Shu), Chinese empress of the Eastern Wu state
• Tian Yu (or Guorang), Chinese general and politician (b. 171)
• Tiridates II (or Khosrov), Roman client king of Armenia