Some 200 people from Ferrari fan clubs based around Europe made the trip to the Grenoble University Hospital, where a silent vigil was held in support of the seven-time Formula One world champion.
Schumacher, who suffered major head injuries in Sunday's accident in the French Alps, enjoys a special place in the hearts of all Ferrari fans, having won the world drivers' title for five successive years between 2000 and 2004 while driving for the Scuderia.
Seventy-two of his record 91 grand prix wins also came at the wheel of Ferrari cars, and the Italian team have been at the forefront of the efforts to pay tribute to the stricken champion, whose condition was described earlier this week as critical but stable.
A Ferrari statement read: "This is a special day for Ferrari and all its fans as it is Michael Schumacher's birthday.
"At the moment, he is tackling the most important fight of his life and therefore we want to send him very special wishes.
"Everyone at Ferrari, from president Luca di Montezemolo and team principal Stefano Domenicali, who are in touch all the time with Michael's family and those closest to him, are continuously watching how his situation evolves.
"Obviously, today there are double the reasons to wish him all the best.
Supporters who had made the journey to the hospital held a one-minute silence outside on Friday afternoon.
No update was given on Schumacher's condition by the hospital or his management on Thursday and that remained the case on Friday.
Schumacher's family, who have remained at his bedside since the weekend, made their first statement on Thursday in which they insisted the most successful driver in F1 history "is a fighter and will not give up".
Schumacher suffered major brain trauma in the accident which occurred when skiing off-piste in the resort of Meribel in France.
It is believed that his life was saved by his skiing helmet, which split on impact.
Schumacher was initially conscious before deteriorating into a critical condition.
Rescuers were on hand within minutes of the accident and he was airlifted to Grenoble hospital, where neurosurgeons have operated twice to remove blood clots on the brain and reduce swelling.
Doctors have said the impact caused numerous brain injuries including intracranial hematomas (multiple blood clots), bilateral lesions and bruising of the brain.
An initial operation carried out on Sunday to reduce swelling was followed by a second to remove the largest of a number of clots in his brain. Jacqueline Hubert, the Grenoble hospital's director general, said on Tuesday that his condition had started to improve.