Mahinmi, 27, reportedly injured his shoulder during practice on Thursday. He tweeted his disappointment about being so close to starting the tournament and wished his teammates success.
The 6-foot-11 center averaged 3.5 points and 3.3 rebounds last season for the Pacers.
Team France will still have several NBA players in San Antonio Spurs forward Boris Diaw, Portland Trail Blazers forward Nicolas Batum, Orlando Magic guard Evan Fournier and Utah Jazz center Rudy Gobert.
France opens World Cup play on Saturday against Brazil.
- Paul Palladino