The institution was shut by officials of the Revenue Task Force who arrived the campus at about 7:00 on Wednesday morning.
The team sealed the Senate Chamber and the administrative building before proceeding to seal the main gate, leaving the pedestrian gate unlocked.
The team leader, Oladipo Babatunde revealed that the institution owed the state government about N1.8 billion and they had no choice than to seal after the management of OAU refuses to meet up with the deadline issued to them.
According to him, the money owed by the Institution is outstanding unremitted PAYE withholding taxes and developments levy which had become due and payable since year 2015 and 2016.
Meanwhile, Abiodun Olanrewaju, the school's spokesman said it would soon resolve the issue with the state government.
Olanrewaju told newsmen that the debt was inherited from the past administration of the institution.
“I must add this that the present university administration since 2017 has been paying consistently but the backlog of debt inherited from the past administration is what is causing this little problem.
“The school management is assuring the public that it will soon be resolved,” Olanrewaju said.