The reunion will be held from March 14 to 16.
Former pupil Donique Hope (nee Pearsey) will be attending the reunion with her children, who attend the school.
Mrs Hope said she had fond memories of her time at the school in the 1980s.
"I’ve made lifetime friends here.
"I definitely enjoyed my time here and I love that my kids are here."
On her father Gavin Pearsey’s side of the family her children were the third generation to attend the school.
However, on her mother Wendy’s (nee Harper) side the children were the fifth generation to attend.
Mr Pearsey said he attended the school in the 1960s.
He also was still friends with the people he went to school with.
He did all his primary schooling in Mataura as there was no intermediate in Gore, Mr Pearsey said.
Principal Susan Dennison said people could find details of the jubilee on a special Facebook page dedicated to the event or by following a link on the school’s website page.
Former pupils would have the opportunity to share stories about their school days.
There were not many photograph records stored at the school.
"We think that’s because of floods."
The Mataura Museum had been able to supply some.
People should register by June 30.