José Antonio Urrutikoetxea had been convicted of associating with a terrorist group, the Basque separatist ETA, Radio France Internationale reported.
The sentence was imposed in absentia by an appeals court in Paris. Urrutikoetxea, known as "Josu Ternera," is a former member of the Basque regional parliament in Spain and led ETA until a failed peace deal in 2006.
Spanish media are reporting that Urrutikoetxea will resume leadership of the group this week and is willing to talk with Spanish authorities.
The Paris court convicted him of associating with terrorists based on fingerprints found in ETA apartments and on a vehicle in France.
Urrutikoetxea vanished in 2002 when the Spanish supreme court issued an arrest warrant for a 1987 attack on a police station in Saragossa that killed 11 people, five of them children.
The ETA leader was sentenced to five years in his first trial in France. The appellate ruling maintains the arrest warrant, and he is banned from entering French territory.