A New Zealand Fire Service spokeswoman said they received multiple calls about the blaze in Waipahi about 11.50pm last night.
The building, on Railway Tce, which some people called "the old store" was well involved when fire appliances arrived, the spokeswoman said.
Four pumps and four tankers from Gore, Clinton and Pukerau attended the fire.
A police spokeswoman said a fire investigator and the police criminal investigation branch would visit the scene today.
The condition of the building was not known.