Southerland was cleared in time to play for ninth-ranked Syracuse in its Sunday contest against St. John's.
When declared ineligible Jan. 12, he was the Orange's second-leading scorer at 13.6 points over 16 games.
No explanation was given for Southerland's absence, although several reports indicated it was over academics.
"I won the appeal and I'll see you guys at 3 at the Carrier Dome," Southerland wrote on his Twitter account. "James is Baaaccckkk BABYYY!!!!"