Green was found to have sold a jersey - his Independence Bowl jersey - for $1,000 to someone later found to be an agent, according to the NCAA.
"According to NCAA rules, an agent is any individual who markets or promotes a student-athlete," the NCAA said in a release.
Georgia is appealing, but Green will be ineligible during that process. That basically ensures that the star receiver will miss Saturday's game at South Carolina, because if the suspension was reduced it would likely only be by two games.
If Green misses a full four games, he would be eligible to return for Georgia's Oct. 2 game at Colorado.
"I want to apologize to my coaches, teammates, and the Georgia fans for the mistake in judgment," Green said in a statement released by the school. "I very much regret all that has taken place and the distraction that's been caused. I've learned a valuable lesson and hope others can learn from my mistake. I can only focus my attention now on practicing and looking ahead to getting back with my teammates as quickly as possible."
Georgia head coach Mark Richt said in a statement that was "disappointed with the outcome."
"However, we have games to play and that's where our focus needs to be in the coming days and weeks," Richt said "Other players will have to step forward and I'm confident they will do that."
Here's the full release from the NCAA:
University of Georgia football student-athlete A.J. Green must miss four games as a condition of becoming eligible to play again, according to a decision today by the NCAA student-athlete reinstatement staff.
The university declared the student-athlete ineligible for violations of NCAA agent benefits rules. According to the facts of the case submitted by Georgia, the student-athlete sold his Independence Bowl game jersey to an individual who meets the NCAA definition of an agent. Green has repaid the $1,000 value of benefits to charity.
During the reinstatement process, the NCAA staff reviews each case on its own merits based on the specific facts. Staff decisions are made based on a number of factors including guidelines established by the Committee on Student-Athlete Reinstatement, the student-athlete¹s responsibility for the violation, as well as any mitigating factors presented by the university.
The university can appeal the decision to the Division I NCAA Committee on Student-Athlete Reinstatement, an independent committee comprised of representatives from NCAA member colleges, universities and athletic conferences. This committee can reduce or remove the condition, but it cannot increase the staff-imposed conditions. If appealed, the student-athlete remains ineligible until the conclusion of the appeals process.