1366
| Years | 
|---|
| Millennium | 
| 2nd millennium | 
| Centuries | 
| Decades | 
| Years | 
| 1366 by topic | 
|---|
| Leaders | 
  | 
| Birth and death categories | 
| Births – Deaths | 
| Establishments and disestablishments categories | 
| Establishments – Disestablishments | 
| Art and literature | 
| 1366 in poetry | 
| Gregorian calendar | 1366 MCCCLXVI  | 
| Ab urbe condita | 2119 | 
| Armenian calendar | 815 ԹՎ ՊԺԵ  | 
| Assyrian calendar | 6116 | 
| Balinese saka calendar | 1287–1288 | 
| Bengali calendar | 772–773 | 
| Berber calendar | 2316 | 
| English Regnal year | 39 Edw. 3 – 40 Edw. 3 | 
| Buddhist calendar | 1910 | 
| Burmese calendar | 728 | 
| Byzantine calendar | 6874–6875 | 
| Chinese calendar | 乙巳年 (Wood Snake) 4063 or 3856 — to — 丙午年 (Fire Horse) 4064 or 3857  | 
| Coptic calendar | 1082–1083 | 
| Discordian calendar | 2532 | 
| Ethiopian calendar | 1358–1359 | 
| Hebrew calendar | 5126–5127 | 
| Hindu calendars | |
| - Vikram Samvat | 1422–1423 | 
| - Shaka Samvat | 1287–1288 | 
| - Kali Yuga | 4466–4467 | 
| Holocene calendar | 11366 | 
| Igbo calendar | 366–367 | 
| Iranian calendar | 744–745 | 
| Islamic calendar | 767–768 | 
| Japanese calendar | Jōji 5 (貞治5年)  | 
| Javanese calendar | 1279–1280 | 
| Julian calendar | 1366 MCCCLXVI  | 
| Korean calendar | 3699 | 
| Minguo calendar | 546 before ROC 民前546年  | 
| Nanakshahi calendar | −102 | 
| Thai solar calendar | 1908–1909 | 
| Tibetan calendar | 阴木蛇年 (female Wood-Snake) 1492 or 1111 or 339 — to — 阳火马年 (male Fire-Horse) 1493 or 1112 or 340  | 
Year 1366 (MCCCLXVI) was a common year starting on Thursday of the Julian calendar.