The prosecution demanded life sentences, saying 'morally, the FIS was alone responsible for the events of June' last year when 85 people were killed in street violence.
The trial was boycotted by defence lawyers, who said they would appeal to the supreme court whatever the sentence. It was closed to foreign journalists and observers.
In Algiers, a circular from the FIS warned the court it alone would be responsible for whatever happened after its judgment.
Another FIS official, the former mayor of Algiers, Kamel Guemazi, was jailed for six years and four others received four years each.