Elisabeth Schumacher, 55, the mother of Michael and Ralf, died in a hospital in Cologne, Germany, early Sunday.
She had slipped into a coma following a fall at her home last Saturday and underwent an emergency operation.
Both brothers will, however, take part in the San Marino Grand Prix on Sunday.
Ralf's spokesman Thomas Hofmann said: "I can confirm that Ralf and Michael's mother died this morning."
"That's the only thing we can say, please respect that this is a private matter."
Five-times world champion Michael will start the race in pole position, with Ralf second.
Ralf arrived at the Imola track on Sunday morning dressed in a black top and dark blue jeans.
The brothers had flown to Cologne to visit their mother after Saturday's qualifying session. They arrived back in Imola late on Saturday night.