The 22-year-old Frenchman suffered a huge impact at the Raidillon swerves from American Juan Manuel Correa’s car at about 170 mph.
A statement from the FIA said that after the occurrence, Hubert was taken to the medical centre and died at local time at 18:35.
The race was ceased after the accident and cancelled a couple of minutes when the potential reality of the mishap turned out to be clear.
Correa was taken to Liege hospital and is in a stable condition, the FIA said.
Renault said in a statement: “Anthoine was a member of the Renault Sport Academy and raced in the FIA Formula 2 Championship, the final ladder to F1.
“As reigning GP3 champion and member of the Equipe de France, FFSA (French Federation of Motorsport), the Frenchman was a huge talent who also brought great energy and positivity to his championship, his teams and the Renault Sport Academy.
“His smile and sunny personality lit up our formidable group of young drivers, who had formed tight and enduring bonds.
“His strong results in F2 this season, including wins on home soil in Monaco and France, inspired not just the other recruits but also the wider Renault Sport Racing group.”