Detectives said Daniel Melendez and Jose Ferrusquilla were carrying 65 pounds of illegal fireworks in their car when they were pulled over.
Police later found more illegal fireworks in one of their homes and determined the men were trying to sell them online.
"The initial price that was negotiated for the 60-65 pounds was somewhere around $1,500, so we're probably looking at somewhere in excess or close to $3,000 worth of illegal fireworks," said Sgt. David McBride of the Ontario Police Department.
Ontario police on Saturday displayed several thousand pieces of fireworks seized from the men.
Ferrusquilla is also facing child endangerment charges for having his 9-year-old son sitting next to the illegal fireworks in the backseat of the car.