The authority, chaired by Judge Kevin Kelly, released its decision last month as thousands of students returned to Dunedin for the new academic year.
Starters Bar, which is in the heart of the city's student quarter, had previously been allowed to open between 12pm and 12am Sunday to Wednesday, and from 12pm to 1am Thursday to Saturday.
OUSA sought an extension of two hours for Thursday, Friday and Saturday nights.
Richard Davison/Stuff
Extending the hours of a student pub will help reduce alcohol related harm, authorities say. Pictured: Revellers enjoy the Otago University Students' Association Hyde Street Party in 2016.