Police say the man entered the bank at about 10:45 a.m. Saturday, approached a teller and demanded money.
The teller complied, giving the man an undisclosed amount of cash.
Police say he fled to the parking lot in a large pickup truck.
The suspect is described as an African American male, 25 to 30 years old, about 6 feet tall with a medium build. He wore a gray hooded sweatshirt, sunglasses, a brown baseball cap with a red logo on it, and blue jeans.
Anyone with information is asked to call Newport Police at (302) 995-1411 or 911.