Organisers are blaming anxiety about Covid-19 among students for a lack of interest.
The week of social events is still expected to be bigger than usual when it begins next week, as students make up for a more subdued start to the year.
The Otago University Students’ Association said in an online post there was a lack of interest, hence the cancellation.
Health concerns could be the underlying cause, the association said.
Events and venues operations manager Jason Schroeder said people were still experiencing Covid or the flu and there was some anxiety about socialising in large groups.
"We cancelled one night of toga to reflect this," Mr Schroeder said.
A second toga party is set to go ahead as planned on Wednesday.
Several social events, including a toga party, were called off before Orientation Week in February due to the Covid-19 red setting.
"We have designed reorientation to provide opportunities for students to be able to get some of the student experiences they missed with the cancellation of some of our Orientation events," Mr Schroeder said.
"This does mean that a wider range of events are on offer than we would normally host."
Events would take place within the Covid-19 protection framework and Covid care packs were available for all students, he said.
