Several hundred union activists, beating drums and making noise by blowing horns, blocked passport control at the terminal, causing hundreds of passengers to miss flights, the Associated Press reporter reported.
Protesters were dispersed and passengers were diverted to another terminal.
The unions are negotiating with the management of the airport in Paris about the reduction of salaries due to the collapse of air traffic in the middle of the pandemic.
The management of three airports in Paris says that the income dropped by 80 percent in 2020 and that it is trying to avoid layoffs by reducing salaries.
The unions announced strikes and protests until Monday, just when many French people are traveling with their families on summer vacation.
Airport management warned passengers of possible delays and interruptions in road traffic during the strike.