Patrick Fiori had a relationship with Julie Zenatti for 8 years. They met during the musical Notre-Dame de Paris where they both had acting roles. The love relation led to an artistic collaboration with Fiori and Zenatti co-writing and co-composing for each other and for others. Zenatti's first and greatest success was "Si je m'en sors" written by Fiori. Despite separating, they remained friends and continued meeting each other. Between 1998 and 2000, Fiori was in a relationship with Canadian-Belgian singer Lara Fabian.
Patrick Fiori married Ariane Quatrefages in June 2008. Quatrefages was a beauty pageant contestant who was crowned Miss Rhône-Alpes 1999 and came fourth in Miss France 2000 elections. The couple had their first child Sevan in 2009. In 2014, the couple had a second son. Ariane co-writes certain songs with her husband Fiori.