The sale of three SeaWorld parks, two Busch Gardens parks and five others is the largest of a string of AB InBev selloffs to help pay for the $52 billion takeover deal that formed it last year.
AB InBev's Busch Entertainment Corporation is the second-largest theme park operator in the United States after Disney and attracts some 25 million visitors every year.
AB InBev chief executive Carlos Brito said the theme parks were "not a core business" for the maker of the world's best-selling beer Budweiser and that the sale was "another important milestone in our commitment to de-leverage the company."
"We are pleased to have reached an agreement with a buyer who understand the industry and has a strategic vision for the business," he said. "We have great respect for BEC's management and employees and know they will continue to prosper under Blackstone's ownership."
Blackstone will pay $2.3 billion in cash and give AB InBev the right to participate in Blackstone's return on its initial investment, an amount that is capped at $400 million.
BEC runs three SeaWorld parks in Orlando, Florida, San Antonio, Texas and San Diego, California as well as two Busch Gardens parks in Tampa, Florida and Williamsburg, Virginia. It also has family entertainment attractions in Orlando, Tampa, Williamsburg and Langhorne, Pennsylvania.
Blackstone said it had "long admired" the theme parks and planned to invest in and grow the company.
"We are delighted to be investing in a company with such iconic brands, irreplaceable assets and strong growth prospects," said senior managing director Michael Chae.