The reinstatement was first reported Wednesday night by The Post-Standard of Syracuse.
He will be on the roster for Saturday's game against St. John's at Madison Square Garden.
The school did not provide further details in its statement, citing university policy and federal student privacy laws.
The second-ranked Orange (22-1, 9-1 Big East) went 2-1 without Melo, beating Cincinnati and West Virginia after losing to Notre Dame in the center's first game on the sideline.
The academic issue occurred in the first semester, a source previously told ESPN.com's Andy Katz.
Melo was allowed to practice with the team during his suspension. He is averaging 7.2 points and 5.7 rebounds in 22.6 minutes per game.
Information from ESPN.com's Andy Katz contributed to this report.