Wearing a dark suit and tie with a white shirt, Sarkozy bowed his head but otherwise remained motionless as the verdict was read out.
He was accused of trying to glean confidential information from a judge by using a so-called “burner” mobile phone and false name of Paul Bismuth.
Sarkozy, who is set to appeal, had risked up to a decade in prison and a fine approaching the equivalent of £1million.
Also found guilty were his lawyer, Thierry Herzog, 65, and Gilbert Azibert, the 73-year-old retired judge who was said to have been bribed.
All received the same punishment with two years suspended. French prosecutors accused the three of working out a corruption pact to advance their careers. Sarkozy, who led France for a single five-year term up to 2012, told the court he “never committed the slightest act of corruption” and vowed to go “all the way” to clear his name.