George Lucas says Star Wars would live on and flourish with Disney
Disney is buying Lucasfilm, the company behind the Star Wars films, from its chairman and founder George Lucas for $4.05bn (£2.5bn).
Lucas said: "It's now time for me to pass Star Wars on to a new generation of film-makers."
In a statement announcing the purchase, Disney said it planned to release a new Star Wars film, episode seven, in 2015.
That will be followed by episodes eight and nine and then one new movie every two or three years, the company said.
The last Star Wars film was 2005's Revenge of the Sith, and Disney said it believed there was "substantial pent-up demand".
Disney will pay about half in cash and half in stock, issuing 40 million Disney shares in the transaction.
The deal follows Disney's acquisitions of Pixar studios for $7.4bn in 2006 and Marvel comics for $4.2bn in 2009.
"Our valuation of Lucasfilm is roughly comparable to the value we placed on Marvel when we announced that acquisition in 2009," Disney said, adding that the valuation was almost entirely driven by the Star Wars franchise.
George Lucas launched Lucasfilm in 1971 and the first Star Wars film was released in 1977.
"For the past 35 years, one of my greatest pleasures has been to see Star Wars passed from one generation to the next," Lucas said.
"I've always believed that Star Wars could live beyond me, and I thought it was important to set up the transition during my lifetime."
Lucas will continue as a creative consultant.
Kathleen Kennedy, currently co-chairman of Lucasfilm, will become president of the firm and will be the executive producer on the new Star Wars films.
When the later Star Wars films were released in the 1990s and 2000s, although they did well at the box office, they were generally not well-received by fans.
But Josh Dickey, film editor at Variety magazine in LA, said that Disney was a "great fit" to update Star Wars.
"They're so good at branding and brands. They're so good at working with existing intellectual property and making it resonate with fans and marketing it very well," he told BBC World Service radio.