Gueant worked closely with Sarkozy for a decade and served as interior minister from 2011 to 2012.
The case against him and several others dates back to between 2002 and 2004 when Michel Gaudin, a former national director general of the police, made monthly payments to Gueant of 10,000 euros from an expense account for police investigations.
A total of 210,000 euros was handed out, with Gueant keeping half and the rest distributed among the co-accused.
Guedin was given a 10-month suspended sentence, while three other members of Sarkozy's team were given short suspended jail terms and fined.
Gueant's lawyers have said they will appeal his conviction.