But he immediately appealed the ruling on Friday which then blocked his disqualification from office.
Juppe, one of President Jacques Chirac's closest allies, was found guilty by the court in the western Paris suburb of Nanterre of "taking illegal benefits" while Chirac was mayor of Paris and Juppe managed the finances at city hall.
Juppe - who heads the pro-Chirac Union for a Popular Movement (UMP) party and is also mayor of the south-western city of Bordeaux - was one of 27 people who stood trial last year on charges of organising the illegal payment of staff salaries at the UMP's precursor, Chirac's Rally for the Republic (RPR).
His conviction automatically carried a disqualification from holding public office but his appeal puts the penalty on hold, leaving the 58-year-old Juppe in political limbo and unable to pursue his ambitions to succeed Chirac as president in 2007.
Among the other defendants, former RPR official Louise-Yvonne Casetta, 62, was handed a 14-month suspended sentence for her involvement in the scam. Former party treasurer Jacques Boyon was handed a 14-month suspended sentence.