|Millennium:||1st millennium BC|
|Centuries:||2nd century BC – 1st century BC – 1st century|
|Decades:||50s BC 40s BC 30s BC – 20s BC – 10s BC 0s BC 0s|
|Years:||26 BC 25 BC 24 BC – 23 BC – 22 BC 21 BC 20 BC|
|23 BC by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishments and disestablishments categories|
|Establishments – Disestablishments|
|Gregorian calendar||23 BC
|Ab urbe condita||731|
|English Regnal year||N/A|
— to —戊戌年
|- Vikram Samvat||34–35|
|- Shaka Samvat||N/A|
|- Kali Yuga||3079–3080|
|- Ǹrí Ìgbò||-1022–-1021|
|Iranian calendar||644 BP – 643 BP|
|Islamic calendar||664 BH – 663 BH|
|Juche calendar||N/A (before 1912)|
|Julian calendar||23 BC|
|Minguo calendar||1934 before ROC
|Thai solar calendar||521|
|Wikimedia Commons has media related to: 23 BC|
Year 23 BC was either a common year starting on Saturday or Sunday or a leap year starting on Friday, Saturday or Sunday (link will display the full calendar) of the Julian calendar (the sources differ, see leap year error for further information) and a common year starting on Friday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Augustus and Varro (or, less frequently, year 731 Ab urbe condita). The denomination 23 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.
By place 
Roman Empire 
- Caesar Augustus becomes Roman Consul for the eleventh time. His partner is Aulus Terentius Varro Murena.
- Augustus relinquishes the position of consul, retains that of tribune of Rome and assumes that of Princeps, or "First Citizen." (see Roman Empire).
- Augustus gets seriously ill: he gives Agrippa his signet ring and grants him the title imperium pro consule.
- The Nubians, led by queen Candace Amanirenas, take the initiative against the Roman Empire, and attack the Roman province of Egypt moving towards Elephantine.
- Herod the Great builds a palace in Jerusalem and the fortress Herodian in Judaea. He also marries his third wife, named Mariamne, the daughter of high priest Simon.
- Following coinage reform, the as was struck in reddish pure copper, instead of bronze. The denominations of sestertius and dupondius were introduced as large bronze coins.
- In response to Meroe's incursions into Upper Egypt, the Roman legions move south and raze Napata. (Early history of Sudan).
By topic 
- The Roman writer, architect and engineer Vitruvius finishes writing De Architectura (known today as The Ten Books of Architecture), a treatise in Latin on architecture, and perhaps the first work about this discipline.
- The Roman poet Horace publishes the first three books of Odes.