The 26-year-old Brazilian moves to the Mestalla for an undisclosed fee, believed to be around £10million, as Arsenal boss Arsene Wenger trims his squad.
Gabriel sustained a serious knee injury in Arsenal's final Premier League game of last season and did not feature in pre-season.
He scored one goal in 64 appearances for the north London club.
Spanish club Valencia announced the signing in a statement on their official website
It read: "Valencia have reached an agreement with Arsenal for the transfer of ..
Gabriel Paulista.
"The Brazilian player has signed for the next five seasons until June 30, 2022, with a termination clause of 80 million euros."
Gabriel could be the first of a number of departures at the Emirates, with Lucas Perez, Calum Chambers and Joel Campbell also linked with moves away
Source : PA
Source: PA