The Repsol Honda Team rider fractured his left little finger in a training accident last weekend and had surgery to fix it last week.
In a chat with MCN, Marquez confirmed that he was given the ok to race this weekend.
"Today I underwent another examination by Dr. Mir, and he confirmed that the wound is healing well and looking good," said Marquez.
"He took off the cast that they had put on and now I have begun to do some physiotherapy work with some active and passive movements. My finger will be checked at Jerez after every session and the bandages will be changed.
"I am very motivated for this Grand Prix, because it is the first of the year in Spain, there are my home fans there and I have some good memories from previous years! It's a pity about the injury, but I hope that it doesn't affect me too much and that I can get a great result in front of the fans," he added.