The 34-year-old actor, known for his roles in BBC television production "The Tudors" and the films "Match Point" and "Bend It Like Beckham", was not in court for the ruling.
Rhys Meyers was arrested in a bar at Paris's Charles de Gaulle airport in June 2009 and charged with being drunk and disorderly after he struck a barman and insulted three police officers.
The court in suburban Bobigny said Rhys Meyers was "extremely aggressive" and threatened to pay to have the officers and their families killed.
After being taken into custody and sobering up, he apologised to the officers and said he was suffering from alcoholism, the court said. He admitted to being drunk but said he did not fully recall the events.
The court said Rhys Meyers had compensated his victims in the case, without providing details.
His lawyer Vincent Toledano had pleaded for the court to dismiss the charges, saying Rhys Meyers was "a fragile man" and a "fairly weak person" who "suffers... from his demons."
He later described the sentence as "harsh" and said Rhys Meyers had been "harmed by his fame".
An Irish court in 2007 dropped similar charges against Rhys Meyers after he was arrested for being drunk and disorderly at Dublin airport.