The 23-year-old forward has signed a five-year deal with the Club and joins from French side Lorient for an undisclosed fee.
The Ghana international arrives at Villa Park following the acquisitions of fellow Ligue 1 players Jordan Amavi and Idrissa Gueye.
Manager Tim Sherwood said: "I'm really pleased to bring Jordan to the football club.
"He is a fantastic young player who is perfectly suited to the Premier League."
Ayew completed his medical at Bodymoor Heath this morning before meeting his new team-mates for the first time.