The winning ticket from Saturday's drawing was sold at USA Tobacco shop on Hamner Avenue in Norco. Lottery officials said the ticket matched all six numbers.
Numbers drawn Saturday were: 7, 10, 11, 21, 32 and the Mega number was 5.
The player has the option of receiving the $25 million jackpot in 30 graduated annual installments or a lump sum payment of $11.4 million, both before federal taxes.
A ticket matching five numbers but missing the Mega number was also sold at a gas station in Agoura Hills on Canwood Street. That ticket is worth $33,650.
The drawing was the 18th since the last time a ticket with all six numbers was sold.
The odds of matching all five numbers and the Mega number is 1 in 41,416,353, according to the California Lottery. The jackpot for Wednesday's drawing will be $7 million.
In Friday's Mega Millions drawing, a ticket sold at a Chino gas station matched five numbers. That ticket is worth $2.2 million.
City News Service contributed to this report.