The Veltins-Arena stadium in Gelsenkirchen, home to Schalke 04 soccer club, can hold up to 65,000 people.
The Klitschko-Haye fight had earlier been planned to be held at the Stamford Bridge stadium in London, home to Chelsea FC, the website said.
'Dr. Steelhammer' Klitschko (52-3, 46 KOs) earlier said he was glad the fight has been scheduled, as he was getting tired of "listening to trash talks" from Haye (22-1, 21 KOs).
The 28-year-old Briton has been accusing Wladimir of only fighting cowards, and recently pledged to knock Klitschko out, and take his IBF and WBO belts home to London.