|Millennium:||1st millennium BC|
|368 BC by topic|
|Gregorian calendar||368 BC|
|Ab urbe condita||386|
|Ancient Egypt era||XXX dynasty, 13|
|- Pharaoh||Nectanebo I, 13|
|Ancient Greek era||103rd Olympiad (victor)¹|
|Balinese saka calendar||N/A|
|Chinese calendar||壬子年 (Water Rat)|
2329 or 2269
— to —
癸丑年 (Water Ox)
2330 or 2270
|Coptic calendar||−651 – −650|
|Ethiopian calendar||−375 – −374|
|- Vikram Samvat||−311 – −310|
|- Shaka Samvat||N/A|
|- Kali Yuga||2733–2734|
|Iranian calendar||989 BP – 988 BP|
|Islamic calendar||1019 BH – 1018 BH|
|Minguo calendar||2279 before ROC|
|Thai solar calendar||175–176|
−241 or −622 or −1394
— to —
−240 or −621 or −1393
Year 368 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Tribunate of Cornelius, Praetextatus, Structus, Capitolinus, Crassus and Cicurinus (or, less frequently, year 386 Ab urbe condita). The denomination 368 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.
- While the previous year's intervention by the Macedonians in Thessaly is successful, after the Macedonian troops withdraw, Alexander of Pherae treats his subjects as cruelly as before. So the Thessalians seek Thebes' support. Pelopidas is sent to their assistance, but is treacherously seized and imprisoned.
- In response, Epaminondas is reinstated in command of Theban troops and leads the Theban army into Thessaly, where he outmanoeuvres the Thessalians and secures the release of Pelopidas without a fight.
- At the instigation of Alexander's brother-in-law, Ptolemy of Aloros, Alexander II of Macedon is assassinated during a festival. Although Alexander's brother, Perdiccas III becomes the next king, he is under age, and Ptolemy is appointed regent.
- Plato's Republic is completed. It lays down the rules for an ideal, righteous society and suggests that kings ought to be philosophers (or at least taught by philosophers).
- Alexander II, King of Macedonia (assassinated)