The court of appeal sitting in Abuja has ordered members of the Academic Staff Union of Universities (ASUU) to immediately resume duty.
ASUU has been on strike since February over demands largely bordering on the allowances and salaries of its members.
Meetings between the union and the federal government have been fruitless.
The national industrial court had asked ASUU to immediately resume lectures, pending the determination of a suit brought by the government.
But the union challenged the decision of the court, filing an appeal at the appellate court.
On Friday, the appeal court held that the union must first call of its strike — in obedience to the lower court — before it will entertain its appeal.
The court gave ASUU seven days to appeal against the judgment of the lower court.
On Tuesday, the federal government registered the Congress of Nigerian University Academics (CONUA) in a move seen as an attempt to whittle down the influence of ASUU.