The state's lottery said a Powerball ticket worth $231 million was sold at the Acme store at 460 E. Main Street in Middletown.
The ticket matched all five numbers and the Powerball in Monday night's drawing. The jackpot has a cash value of $105 million.
The winning numbers were 7-24-37-42-57 and the Powerball was 5.
The winner has not yet come forward.
The person with the winning ticket is urged to sign the back and keep it in a safe place until they can begin the claims process.
It's the first time someone has hit the Powerball jackpot in Delaware since 2016.
The odds of matching all five numbers and the Powerball number are 1 in 292.2 million, according to the Multi-State Lottery Association. The overall chance of winning a prize is 1 in 24.9.
Powerball is played in 45 states, the District of Columbia, Puerto Rico and U.S. Virgin Islands.