Only half of the usual services were running on the RER A and B train lines on Thursday due to the strike that had been called by the CGT union.
The industrial action, which is set to cause disruption to tens of thousands of commuters and travellers passing through the capital's airports, affects two major commuter lines in the French capital.
RER A passes through the centre of the city from east to west and serves the capital's financial hub at La Defense to the west of Paris. It is one of the busiest lines in Europe.
RER B runs from north to south and serves both the city's airports at Orly and Charles de Gaulle. Passengers are advised to allow more time to get to the airports on Thursday.
All passengers on the RER B will have to change at Gare du Nord.
Paris transport chiefs RATP say extra trains and bus services will be laid on to try and minimize the disruption.
The strike will also have a knock on effect on the Metro, with thousands of RER commuters set to take to the city's underground network instead.
Previous strikes on the RER A have prompted scenes of chaos at Metro hubs like St Lazare.
Thursday's strike has not been called to push for high wages, better working conditions or any of the other usual causes, but is being held in support of former employees at the Goodyear tyre plant in the northern city of Amiens.
Eight workers were handed prison sentences last month for their role in the "boss-napping" of two of the company executives during a labour dispute in 2014.
The two bosses were held against their will for 30 hours, but the tough sentences outraged unions and many on the left, who demanded that the case needed to be seen in the context of a labour dispute, with over 1,000 workers facing the axe.
The motive for the strike has given Parisians even more reason to feel cheesed off on Thursday.
"Strike on the RER B, Motive? Solidarity with Goodyear workers. Seriously! said A.Menard on Twitter.
Another named Marine tweeted: "Solidarity? So to defend 10 people,the logic is to piss off thousands???"
"No surprise that the RER A and RER B are showing solidarity with the people who kidnapped their boss, when they kidnap passengers," said Biba Ash.
The CGT wants the government to intervene and quash the convictions.