The newly-promoted Premier League club announced Patricio had signed a four-year deal, subject to international clearance.
The 30-year-old has won 70 caps for his country.Patricio came through Sporting’s youth system before making his debut in 2006.
He leaves Sporting having made 460 appearances, making him second on the Primeira Liga club’s all-time list.
Patricio becomes Nuno Espirito Santo’s second summer capture following the signing of Mexico forward Raul Jimenez.