A letter authored by the Academy's president David Rubin and CEO Dawn Hudson condemned Will's "unacceptable and harmful behaviour".
It read: "The 94th Oscars were meant to be a celebration of the many individuals in our community who did incredible work this past year; however, those moments were overshadowed by the unacceptable and harmful behavior we saw Mr Smith exhibit on stage.
"During our telecast, we did not adequately address the situation in the room. For this, we are sorry. This was an opportunity for us to set an example for our guests, viewers and our Academy family around the world, and we fell short — unprepared for the unprecedented."
The statement concluded: "Today, the Board of Governors convened a meeting to discuss how best to respond to Will Smith's actions at the Oscars, in addition to accepting his resignation. The Board has decided, for a period of 10 years from April 8, 2022, Mr Smith shall not be permitted to attend any Academy events or programs, in person or virtually, including but not limited to the Academy Awards."