The US giant has not disclosed financial terms of the deal, which is expected to be completed by the end of September.
Mythic is to be renamed EA Mythic. It developed the highly rated Dark Age Of Camelot and is currently working on another keenly anticipated fantasy-themed title called Warhammer Online: Age of Reckoning.
Upon completion of the acquisition, Mark Jacobs, the president, chief executive officer and co-founder of Mythic, will become vice president and general manager of EA Mythic.
Rob Denton, the vice president, chief operating officer and other co-founder of Mythic will assume the role of vice president and chief operating officer of EA Mythic.
A 175-strong development team will remain in Fairfax, Virginia.