The Bob's Big Boy restaurant in Mapunapuna was heavily damaged by a fire early Monday morning.
The blaze at the popular restaurant on Pa'a Street was first reported at 2:49 a.m. by a police officer who happened to be driving by.
The fire started in the kitchen, fire officials said. It took 36 firefighters and at least six companies almost an hour to bring it under control.
"Because of the construction of the building, right now, we are having a difficult time as far as getting to the seed of the fire," Capt. Robert Main said.
The cause has not been disclosed.
Fire officials estimate the blaze caused $1.5 million in damage.
"I was shocked, and I don't know what to say after a while and I can't move you know. I was stunned," restaurant manager Jesus Corpuz said.
Corpuz said the restaurant is insured and will be rebuilt. The employees are meeting Tuesday with the owners to discuss what will happen to them in the meantime.