Michel Maure, who claimed to be one of the world's best plastic surgeons, was arrested in Spain last month after going missing while awaiting the verdict of his trial in the southern French city of Marseille.
The sentence was handed down in absentia and Spanish authorities were expected to transfer him to French custody within the next two weeks, his lawyer Dominique Ramirez said.
A document seen by AFP and dated from September 3 shows that the Spanish National Audience, the country's highest criminal court, has decided to "hand (Maure) over to the French authorities."
A judicial official said Monday that once such a decision is taken, officials have 10 days in which to extradite the prisoner, which means he should be returned to France by Saturday.
Maure, 59, was given a four-year sentence, 12 months suspended, on charges of false advertising, deception, and causing involuntary injury.
"He engaged in a type of garage surgery that showed a total contempt for others," said judge Vincent Turbeaux, who cited the doctor's "particularly shocking" attitude.
Close to 100 of his patients had lodged complaints against him, describing excruciatingly painful procedures carried out in unsanitary conditions at his clinic.
In rendering the verdict, Turbeaux noted that Maure did not have a qualified nurse assisting him during surgery.
"By doing this, Michel Maure knowingly put the lives of his patients at risk," he said.
The plaintiffs were awarded compensation ranging from 1,000 euros (1,400 dollars) to 7,586 euros, with the total sum equal to tens of thousands of euros.
"The masks have fallen," cheered lawyer Jerome Rambaldi, representing about a dozen of Maure's clients.
"We can only hope that pseudo-cosmetic surgeons will remember this conviction and will not engage in the same type of practices," he said.
Maure was convicted of falsifying his qualifications to lure clients to his clinic where there was little regard for basic safety rules.
Many of Maure's mostly female patients decribed his methods as "violent." He carried out painful procedures, such as liposuction or the insertion of breast implants, under a simple local anaesthetic, they said.
His patients complained of chronic pain and infections. Several have had to undergo reparatory surgery.
Maure, who claimed to be the "victim of a plot," was in 2007 struck off France's medical register.
Maure's lawyer said he would appeal the verdict, describing it as "extremely harsh" and argued that his client did not have the financial means to make the compensation payments.
"Since he was forced to end his practice four years ago, he has had no source of revenue," said Ramirez.
Some of the patients said they were disappointed with the ruling.
"We were expecting more but the important thing is that he can no longer practice when he gets out of prison," said Nadia, who underwent surgery for breast implants at Maure's clinic.
Sandrine, 25, who suffered complications from breast-implant surgery, said the damages she was awarded were not enough.
"I did not get enough for a new operation," she lamented.