Fourteen jurors were selected to sit in on the trial, which is expected to last between 18 and 24 months.
The trial will begin more than six years after Operation SharQc dismantled, or drove further underground, a large part of the Hells Angels' organization in Quebec.
In 2009, 156 people were arrested in the massive SharQc sting on various charges including murder, conspiracy to commit murder, drug trafficking and gangsterism.
In the years since, 101 have pleaded guilty, while 31 others were released in 2011 after a judge ruled there were unreasonable delays in their cases.
Three people have died since being charged, while eight others are still at large.
Only 12 of the 156 chose to go to trial. Ten of those 12 will face the jury in the mega-trial beginning Aug. 3.
The final two accused have a trial date set for January 2016.