The second occurred between Lille and Arras, ICI France reported.
Photos showed large queues at both railway stations, while stranded passengers demanded refunds on social media.
In a statement on X, Eurostar offered its apologies to customers affected.
“Due to a person struck by a train near Lille Europe, we are expecting delays and cancellations to our services this evening,” it said.
“We advise changing your journey for a different travel date.”
One train leaving London at 2.31pm was supposed to arrive in Paris at 5.57pm but was delayed for four hours and was not expected to get there until almost 10pm.
Other trains departing from London, including the 4.01pm, 6.01pm, and 8.01pm services, were cancelled. Trains departing from Paris suffered similar disruption.
Millie Race said in a post on X: “Hey, we have been on the ES 9032 from London to Paris for seven hours; still stopped and not sure when we will be able to make it to Paris. Will we be able to get full compensation for our journey?”
Naomi Sanger, from Snodland, told Kent Online she boarded the 4.31pm at Gare Du Nord but it never departed. She was left stranded at the station.
She posted on X: “The supplies of food and drinks are running out, air con is not working, coffee machine broken as is the card machine! Total joke.”
Another passenger, James, posted: “I’m going to need my full ticket refunded and compensation. I’ve been stuck on this train for five hours and there will now be another three-hour delay.”
It is the second time in less than a week that Eurostar services have been disrupted after a person was struck by a train.
Last Thursday NZT, a dozen Eurostar trains from London to Paris were delayed or cancelled after a person was hit on tracks in France.
