The facilities involved are the Greenmount and Loughry campuses of the College for Agriculture, Food and Rural Enterprise, the Belfast Telegraph reported.
Provincial Agricultural Minister Michelle O'Neill, responding to a question from a legislator, said this week the college's food service removed burgers supplied by one company after questions were raised about horsemeat in its ground beef. Samples were sent for testing.
O'Neill said students and staffers at the two campuses were notified about the equine DNA.
Traces of horsemeat have turned up recently in ground beef products sold in Britain and Ireland.