A 70-year-old man from Blue Hill visited the restroom at McDonald's on High Street in Ellsworth on Saturday.
Authorities say when he left the facility, he left his gun sitting on the toilet paper dispenser.
According to Ellsworth Police, that's where the gun was found by the employee.
"We've taken possession of the gun and are currently working with the District Attorney's office as to what charges, if any, will be filed," said Capt. Troy Bires at the Ellsworth Police Dept.
Police say after he realized he had left his weapon, he returned to McDonald's to retrieve it.