| John Peter Marchi | |
| Birth Name: | Ivan Petar Marki (Markić) |
| Birth Date: | 1663 |
| Birth Place: | Republic of Venice |
| Death Date: | 1733 |
| Nationality: | Venetian |
| Other Names: | Giovanni Pietro Marchi |
| Occupation: | Jurist |
| Years Active: | 1680–1733 |
| Known For: | Illyrian Academy |
John Peter Marchi (Italian: Giovanni Pietro Marchi, Ivan Petar Marki; 1663–1733) was a Venetian jurist, member of the Split nobility and founder and president of the Illyrian Academy (Academia Illyrika iliti vam Slovinska). Marchi supported and worked for the liberation of the Sanjak of Bosnia from the Ottoman Empire and conversion of its population to Catholicism.
After he received his PhD in Law in Padua in 1680, Marchi returned to Split where he was a judge and legal advisor. He was librarian of the library of Ivan Paštrić.
Marchi was the most notable member of Marchi noble family. In 1728 he received certificate which confirmed his Roman nobility membership.
See main article: Illyrian Academy.
Marchi was founder, president and member of the Illyrian Academy (Academia Illyrika iliti vam Slovinska). Marchi's intention was to support the capture of the Sanjak of Bosnia from Ottoman Empire and conversion of its population to Catholicism. He believed that Eastern Orthodox Slavs from Bosnia would convert to the religion of the new lord of Bosnia.