Student Melissa Fiering, 18, said she called out to the girl, who bore a striking resemblance to Madeleine McCann in the South of France and said she had a distinctive fleck in her right eye.
The child looked startled at the sound of her name and the "tall, swarthy" man she was with quickly bundled her out of the restaurant.
There has been many reported sighting of the girl but this is only the second time someone has claimed to have identified a girl with the unusual marking in her eye.
French police are inspecting CCTV footage of the student calling to the child at the service station in Montpellier on Friday.
Miss Fiering was in a self-service restaurant called L'Arche on the A9 motorway from France to Spain, listening to music on her mobile phone, when she noticed a child a close by, dancing to the tune.
The student's friend thought she recognised the girl and they walked over to get a closer look. Miss Fiering, from Nijmegen in Holland, said: "When I saw the little girl, I recognised her immediately.
"At first I could not believe it. She was about 6ft away from me. She had the same deformation in her eye.
"I had followed everything about the story on TV and I knew about the 'cat' eye.
"She looked just the same, though she was skinnier about the face and her hair was shorter.
"I called out, 'Madeleine', and she looked up. The man with her was about 6ft tall, with black hair, a black leather jacket and several days growth of stubble.
"When I shouted out, he put on her coat and hat and bundled her away.
"I tried to take a picture of her on my phone, but I did not get it."
Miss Fiering, said: "I wish I had stopped that man. I wanted to pick her up at first, I am so sorry that I didn't do that."
So do I, as I've said before I believe the girl is still alive, who knows what she has endured in all this time?
It does take courage to stand up against a stranger but it was in public and there was a couple of them. There was more at stake than worrying about causing a scene or a few blows to the head messing up yer Rachel hair do.
Maybe she wasn't 100% sure. If this is a true account she will curse herself for years about not acting to save Madeleine.
Have you ever put a small child's hat and coat on them? it doesn't happen in a blur, there was time to take some kind of picture even if it was them walking off.
