The move comes a week after Cosby was convicted of three counts of aggravated indecent assault brought against him by Andrea Constand.
Harvey Weinstein was expelled from the Academy last year after exposés in the New Yorker and New York Times detailed years of sexual harassment allegations against the now-disgraced mogul.
Per Deadline, the Academy voted on Tuesday to expel both Cosby and Polanski in their continued efforts to hold the personal conduct of their members to a higher standard. Cosby is now awaiting sentencing. Dozens and dozens of women have come forward to accuse Cosby of similar acts over the decades. He has remained a fugitive from USA justice ever since.
According to the Academy's recently updated code of conduct, if miscondut is deemed serious enough, it is refered to the board of governors, the only body that "can make the final determination on whether to suspend or expel a member".
Dead Sea Scrolls: NASA technology helps unravel secrets of ancient manuscripts
The authority said the newly deciphered texts "provide new insights" to archaeologists studying the scrolls. In total, more than 1,000 ancient manuscripts have been discovered from 11 different caves.
The academy said its board members made the latest decision after a vote on Tuesday.
Polanski, a five-time Oscar nominee who won a Best Director award in 2003 for "The Pianist, will nonetheless be able to keep his statute, the Hollywood Reporter said".
His name has since been removed from the television academy website and he has lost an honorary degree from Yale.