|Millennium:||1st millennium BC|
|206 BC by topic|
|Gregorian calendar||206 BC|
|Ab urbe condita||548|
|Ancient Egypt era||XXXIII dynasty, 118|
|- Pharaoh||Ptolemy IV Philopator, 16|
|Ancient Greek era||143rd Olympiad, year 3|
|Balinese saka calendar||N/A|
|Chinese calendar||甲午年 (Wood Horse)|
2491 or 2431
— to —
乙未年 (Wood Goat)
2492 or 2432
|Coptic calendar||−489 – −488|
|Ethiopian calendar||−213 – −212|
|- Vikram Samvat||−149 – −148|
|- Shaka Samvat||N/A|
|- Kali Yuga||2895–2896|
|Iranian calendar||827 BP – 826 BP|
|Islamic calendar||852 BH – 851 BH|
|Minguo calendar||2117 before ROC|
|Seleucid era||106/107 AG|
|Thai solar calendar||337–338|
−79 or −460 or −1232
— to —
−78 or −459 or −1231
Year 206 BC the fifth year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Philo and Metellus (or, less frequently, year 548 Ab urbe condita). The denomination 206 BC 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.
- In the Battle of Ilipa (Alcalá del Río, near Seville) in Spain, the Carthaginian generals, Mago Barca and Hasdrubal Gisco, are defeated by the Roman general Publius Cornelius Scipio. Mago retreats to Gades (modern Cádiz) and then sails for the Balearic Islands.
- The Roman general Publius Cornelius Scipio secures Gades, thus making Roman control of Spain complete. With the effective withdrawal of the Carthaginians from Spain, Hispania becomes a Roman province.
- The city of Italica (north west of modern Seville, Spain) is founded by Scipio as a place to settle for the Roman soldiers wounded in the Battle of Ilipa.
- After having successfully driven the Carthaginians out of Spain, Scipio returns in triumph to Rome and is elected consul. He then prepares to carry the war into Carthage's territory in North Africa.
- Hasdrubal Gisco retreats to the coast and then crosses to North Africa, where he gives his daughter in marriage to Syphax, king of the Numidian Masaesyli tribe, to formalize their military alliance.
- After being an ally of Carthage and fighting with them, Numidian chieftain, Masinissa switches sides when the Carthaginians are driven from Spain and offers to assist Rome. Syphax expels his rival Masinissa and claims himself to be King of Numidia. The Romans support Masinissa's claim to the Numidian throne against Syphax, the pro-Carthaginian ruler of the Masaesyli tribe.
- Arsaces II, king of the Parthians, loses territory in battles with Euthydemus I, ruler of Bactria.
- Antiochus III marches across the Hindu Kush into the Kabul valley and renews a friendship with the Indian king Sophagasenus.
- The war between Macedonia and Rome drags on with no decided advantage to either side. Rome's interest lies not in conquest, but in keeping Macedon, the Greek city-states and Greek political leagues continually divided and non-threatening.
- Philip V of Macedon is able to take advantage of Roman inactivity. After sacking Thermum, the religious and political centre of Aetolia, Philip is able to force the Aetolians to accept a peace treaty based on his terms.
- Ziying, ruler of the Qin Dynasty, surrenders to Liu Bang, leader of a popular revolt. This marks the end of the Qin Dynasty and the principality that would later become the Han Dynasty established by Liu. However, in order to secure his position throughout China, Liu Bang becomes engaged in a civil war with the warlord, General Xiang Yu, until 202 BC, known as the Chu-Han contention.
- The Jian and Dao swords were created during this time (approximate date).
- Chrysippus, Greek Stoic philosopher (approximate date)
- Han Cheng, Chinese ruler of the Eighteen Kingdoms
- Han Guang, Chinese ruler of the Eighteen Kingdoms
- Scerdilaidas, Illyrian king of the Ardiaean Kingdom
- Yi (or Huai II), Chinese ruler of the Chu State
- Ziying, Chinese ruler of the Qin Dynasty