It's the eleventh year the show has taken place and this year it will be at the Searsport High School from 9 a.m. to 2 p.m.
There will also be craft vendors and food, and firefighters said the money raised goes back to the fire department.
"It helps offset the costs for the town, as far as stuff that we buy for the department...we've bought washing machines, a thermal camera," said Searsport Fire Dept. Captain James Morton.
He said the event is free to attend and $10 to register a car.
Firefighters said every year they get between 70 and 100 cars in the show.