Jimenez joins the Cherries on-loan for the season with an option to buy.
Bournemouth’s President of Football Operations, Tiago Pinto, spoke with afcb.co.uk: “Álex is a highly regarded young player who has already shown great promise at AC Milan.
“We are delighted to bring a player with such talent into the club and we believe he will be a strong addition to our squad. We’re looking forward to working with him once he returns from international duty with Spain.”
Jimenez also commented: "I’m very happy. I'm excited about this project and that they've welcomed me so well. I can't wait to start training with the team and playing with the team.
"It has always been one of my dreams to play in the Premier League and as long as I can fulfill a dream, I will be happy."