An appeals court issued the sentence against Jamal Dati, after prosecutors challenged his initial six-month suspended term handed out in February.
Mr Dati's lawyer said his client had been singled out for his family ties, and says he will appeal.
In July Ms Dati steered through parliament a law on tougher sentences for repeat offenders. Mr Dati had previous convictions.
He was fined for drugs use in 1995 and received a prison sentence for drug trafficking in 2001.
Mr Dati's lawyer, Frederic Berna, suggested his client was meted harsher treatment just because he was the brother of the justice minister.
He added that Mr Dati was "a drug addict who had problems when he was a teenager and who suffered greatly from the death of his mother".
A second brother, Omar Dati, is under investigation for marijuana trafficking.
Last Mod: 23 Ağustos 2007, 12:37