The 19-year-old student said she was stopped in a McDonald's on Seven Sister's road in Holloway, North London.
McDonalds has apologised and said the security guard responsible had been suspended.
In footage of the incident, the woman, who asked not to be named, asks a guard why she cannot be allowed to queue.
“It’s just a matter of taking it off," he says.
She responds: “It’s not just a matter of taking it off. I wear this for religious reasons and I’m not ashamed of it, and I will stand in line and I will get the food I want, because this isn’t okay."
When another member of the public intervenes to defend the teenager, the guard says: “It’s none of your business.”
The woman says “this is f****** ridiculous”. A member of staff tells her “don’t be rude” and asks her to stop filming, which she refuses to do.
When staff eventually agree to serve her, she says: “I don’t want want anything any more.”
In an emailed statement to The Independent, McDonald's said it "has no policy which restricts or prevents anyone wearing a hijab, or any other religious attire, from entering our restaurants".
It added: "We welcome customers of all faiths and sincerely apologise for this situation.
"We are taking this matter very seriously and are addressing the situation with the individuals involved; the security guard, from a third party company, has been suspended."
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