| Native Name: | مرعشیون |
| Conventional Long Name: | Marashiyan Dynasty |
| Iso3166code: | omit |
| Era: | Middle Ages |
| Government Type: | Monarchy |
| Year Start: | 1359 |
| Year End: | 1596 |
| P1: | Afrasiyab dynasty |
| S1: | Safavid Empire |
| Image Map Caption: | Map of the Marashiyan dynasty |
| Capital: | Amol, Sari, Vatashan |
| Common Languages: | Mazanderani |
| Religion: | Twelver Shi'a Islam |
| Leader1: | Mir-i Buzurg (first) |
| Leader2: | Rida al-Din |
| Leader3: | Kamal al-Din I |
| Leader4: | Ghiyas al-Din Ali |
| Year Leader1: | 1359-1362 |
| Year Leader2: | 1362-1392 |
| Year Leader3: | 1362-1392 |
| Year Leader4: | 1404-? |
| Today: | Iran |
The Marashiyan or Marashis (Mazandarani: مرعشیون; Persian: مرعشیان) were an Iranian Sayyid Twelver Shiʿite dynasty of Mazandarani origin, ruling in Mazandaran from 1359 to 1596. The dynasty was founded by Mir-i Buzurg, a Sayyid native to Dabudasht. Their capitals were Amol, Sari, and Vatashan.