A judge ruled the National Rally president must face a charge of circulating “violent messages that incite terrorism or pornography or seriously harm human dignity”.
She is also accused of a second offence related to the sharing of such content that can be viewed by children.
Ms Le Pen posted several graphic images of Isis killings in December 2015, a month after jihadists murdered 130 people in terror attacks in Paris.
One of pictures showed the body of Foley, who was abducted in Syria and executed by Isis in August 2014.
Another showed a man in an orange jumpsuit being run over by a tank, while in the third, captured Jordanian air force pilot Muath Al-Kasasbeh was seen being burned alive in a cage in January 2015.
“Daesh is this!” Ms Le Pen wrote in the tweet, using the terror group’s Arabic name.
A judge in the west Paris suburb of Nanterre has now ruled she should stand trial over the images. She could face up to three years prison and a maximum fine of €75,000 (£66,500) if convicted.
Last year magistrates ordered Ms Le Pen, 50, to undergo psychiatric evaluation to determine if she should go to trial.
The politician, whose party came out on top in France’s European elections last month, has denounced the case as a violation of her freedom of expression.
“I am being charged for having condemned the horrors of Daesh,” she complained last year. “In other countries this would have earned me a medal.”
Ms Le Pen, who has 2.25 million Twitter followers, tweeted the images to a French television journalist who she accused of likening her party to Isis.
She has yet to delete the pictures, which were condemned as “monstrous” by France’s prime minister Manuel Valls.