The graduation ceremony, scheduled for December 9 and 10, would have seen students, mostly postgraduates, from eight faculties obtaining their qualifications.
Acting deputy vice-chancellor for institutional support Lebogang Hashatse said although the university was working on a recovery plan, it was not certain if the graduation would go ahead.
Although NMMU spokeswoman Debbie Derry could not pinpoint the exact number of graduates who might be affected, she estimated that about 1 500 students would miss out on the graduation.
“The graduation ceremony taking place depends on when we go back to class. At this point it might not happen,” she said.
“It has not yet been postponed, but the longer it takes for NMMU to resume classes the less likely it will be.”