A ticket sold in Vermillion matched all five numbers in Saturday night's drawing of Dakota Cash.
The jackpot tops more than $150-thousand.
The South Dakota lottery office is urging the lucky ticket holder to sign the back of the ticket, keep it in a safe place and call the office to validate the ticket.
The winning numbers are 5, 6, 10, 27 and 33.
The odds of winning are one-in-324-thousand.
Winners have 180 days to claim their prize.
The Dakota Cash jackpot starts again at $20-thousand for Wednesday's drawing.