Campana, 20, has put pen to paper on a four-year deal after Palace, preparing for their return to the Barclays Premier League, agreed an undisclosed fee with Sevilla.
Campana captained Spain at the Under-20 World Cup this summer after a foot injury restricted him to just five appearances for Sevilla last season.
The goal-scoring midfielder is excited about playing in the Premier League.
"I'm delighted to become a Crystal Palace player," Campana told Palace Player through an interpreter.
"Over the last two years, I've had some problems with my hometown club, but I'm really excited to play in the Premier League.
"I think it's a good step for me and I'm really excited and looking forward to meet all the boys and start as quickly as possible."
Source: PA
Source: PA