The 20-year-old striker, who scored 16 goals in 34 games in Spain’s Segunda Division last season, has committed to a long-term contract with Alan Pardew’s side.
"I'm very happy to be here to start this new adventure,” Perez told the club’s official website.
"I'm very eager for it to begin and I'm very pleased to play for this magnificent club.
"Any football player would be interested in playing for such a club and I will earn my position to get in the first team."
Perez is Newcastle's first signing of the summer, while reports suggest the side are close to securing a deal for midfielder Jack Colback, who is available on a free transfer after his contract with Sunderland expired.