|Millennium:||1st millennium BC|
|Centuries:||3rd century BC – 2nd century BC – 1st century BC|
|Decades:||130s BC 120s BC 110s BC – 100s BC – 90s BC 80s BC 70s BC|
|Years:||105 BC 104 BC 103 BC – 102 BC – 101 BC 100 BC 99 BC|
|102 BC by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishments and disestablishments categories|
|Establishments – Disestablishments|
|Gregorian calendar||102 BC
|Ab urbe condita||652|
|English Regnal year||N/A|
— to —己卯年
|- Vikram Samvat||-45–-44|
|- Shaka Samvat||N/A|
|- Kali Yuga||3000–3001|
|- Ǹrí Ìgbò||-1101–-1100|
|Iranian calendar||723 BP – 722 BP|
|Islamic calendar||745 BH – 744 BH|
|Juche calendar||N/A (before 1912)|
|Minguo calendar||2013 before ROC
|Thai solar calendar||442|
|Wikimedia Commons has media related to: 102 BC|
Year 102 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Marius and Catulus (or, less frequently, year 652 Ab urbe condita). The denomination 102 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 Republic
- Gaius Marius defeats the Scirii and Teutones at Aix-en-Provence (or Battle of Aquae Sextae).
- The Cimbri defeat the Consul Quintus Lutatius Catulus in the Adige Valley.
- The Chinese under Emperor Wu of Han besiege and capture Kokand of Dayuan in the Hellenistic Ferghana Valley, during a 2 year war with the Yuezhi.