The announcement made no mention of a PS3 version of the game.
The original Mass Effect originally released as an Xbox 360 exclusive in November 2007, followed months later by a PC version in 2008.
Through 2007, Mass Effect on Xbox 360 had sold more than 1.6 million copies.
Few details about the sequel are available. BioWare only said that the second chapter in the planned trilogy will be "dark," and "an even greater peril" awaits.
BioWare CEO Dr. Ray Muzyka added, "We're going to surpass the extraordinary gaming experience we brought our fans in Mass Effect by delivering intensified combat and expanded weapon options as well as increased depth of planet exploration, all while delivering a powerful, emotionally engaging story.
"Mass Effect 2 is shaping up to be an unforgettable RPG-shooter experience, taking players on a non-stop roller-coaster ride filled with stunning plot twists and no-holds-barred action."