Last month, ex-Formula One star Michael emerged from a medically-induced coma.
The 45-year-old had spent 170 days at a hospital in Grenoble, France, following a ski accident in the French Alps last year.
He has since been transferred to a rehabilitation clinic in Lausanne, Switzerland.
The seven-times world champion also used the jet, which still bears Schumacher's initials on the tailplane, more recently for family holidays.
Germany's Bild newspaper reported: "The reasons for the sale are obvious: during his active time as a Formula One driver, Schumi jetted between 300 and 400 hours annually with the aircraft around the world.
"But now everything is different.
"The world of the Schumachers has changed."
At the weekend, it was reported that Schumacher is continuing to make good progress at the Lausanne clinic, sparking rumours he could soon be moved home.
Doctors are said to be hopeful Schumacher will be able to use an advanced wheelchair, which will be controlled by his mouth, within a few weeks.
His wife is reported to have transformed their mansion home in Gland - 30 minutes drive film the clinic - in preparation for the motor-racing legend's return, investing in a personal medical centre, specialist machines, a building for carers to live in and another extension with no steps.
She said: "The German Grand Prix gives me the perfect opportunity to cordially thank you all for the good wishes and positive energies you keep sending to Michael.
"I have to say your sympathies blew us all away.
"It is good to know that together we made it through the hardest time.
"Now we are facing a phase which will presumably take a long time."