"The University accepts that decision and will continue to provide the appropriate assistance to Dorial, just as it does with other students, in helping him grow personally from the many opportunities available to him at OU," the school said in a statement.
Green-Beckham, who was dismissed by Missouri in April after several off-the-field incidents, joined Oklahoma in July.
One of college football's most explosive receivers, Green-Beckham had a breakout sophomore season for the Tigers in 2013 with 59 receptions for 883 yards and 12 touchdowns. He was one of the nation's top recruits in the Class of 2012, ranking No. 3 on the ESPN 150.
Unless a waiver is granted, a player who transfers from one Football Bowl Subdivision school to another must sit out a season. The waiver request on behalf of Green-Beckham was based on the NCAA's "run-off" rule, in which a waiver can be granted if a student-athlete would not have had an opportunity to return to his previous team for reasons outside of his control.
Using this rule, former LSU point guard Anthony Hickey became immediately eligible to play at Oklahoma State after being dismissed by the Tigers.
Green-Beckham's admission to Oklahoma came with specific stipulations, including continued rehabilitation and drug testing, a source told ESPN.com's Brandon Chatmon. Green-Beckham will be subject to a "zero-tolerance" policy, which includes any failed drug test.
Oklahoma believes it has the resources to help Green-Beckham. There was "due diligence" communication between Oklahoma and Missouri coaching staffs before Oklahoma -- including the athletic director and president's office -- approved the transfer.
The 6-foot-6 Green-Beckham was kicked out of Missouri's program after an initial suspension. His troubles included being investigated for allegedly pushing an 18-year-old Missouri student down at least four stairs. No charges were filed, and the case was closed after the student and a roommate declined to press charges.
Green-Beckham also had two marijuana-related arrests during his time at Missouri.
"I appreciate this opportunity from Coach [Bob] Stoops and the University of Oklahoma," Green-Beckham said in a statement issued by the university when he joined the Sooners. "There are people here who will help me build a strong foundation. I've disappointed myself and others in the past. I know that I have a lot of work to do and I'm ready to get started."
The Sooners have been searching for impact players at the receiver position. Sterling Shepard is the lone proven receiver on the roster. OU was one of the finalists for Green-Beckham out of high school, as he made several visits to Norman, Oklahoma, before the 225-pound receiver eventually picked Missouri.
Information from ESPN.com's Brandon Chatmon was used in this report.