A father was quizzed for four hours and then thrown out of the United States in front of his wife and family.
The US authorities have yet to comment on the case
Azar Iqbal, from Cheadle, Greater Manchester, was sent home on a plane at Atlanta last Thursday - despite officials allowing his family through.
He said he was shocked when US police allegedly saw him as a security threat as the group headed for Disneyland.
The US Department for Homeland Security told the BBC it did not comment on individual cases.
A statement for the United States Customs and Border Protection said it denied entry for "thousands of individuals every year on grounds of inadmissibility".
Mr Iqbal said he was also told Asian people needed a special visa.
The incident is alleged to have taken place on the day British airports were put on alert over a reported plot to blow up several Transatlantic flights.
Mr Iqbal said after landing at Atlanta he was questioned by immigration officers who asked if he knew any of the terror suspects arrested in Britain.
He had already been cleared by airport security in Manchester before he boarded the 0900 BST Delta flight.
Mr Iqbal was travelling with his wife Rizwana and their three children Ibrahim, 5, Murvah, 10, and Mohin, 14.
Mr Iqbal's family were allowed to enter the country
He said: "It all started with the immigration man saying he wanted to ask me a couple of questions and they took me and my family to a secure area, where they quizzed me for four hours.
"They asked if I had heard about the arrests in Britain that had happened earlier that day. They said did I know any of the people involved?
"I was really upset and said that there was no way I would know or associate with these people.
"The whole experience was completely demeaning. One of them even said sarcastically 'we didn't tell you to come to America on holiday' after we complained about our treatment.
"They went through all the suitcases including the children's belongings before telling me I was being sent back because I needed a visa despite having a British passport."
A spokeswoman for Delta Airlines said: "This is an issue which you would have to take up with the American authorities.
"Delta is not behind Mr Iqbal being refused entry into the United States."
Mark Hunter, Liberal Democrat MP for Cheadle, said he would be writing to the Home Office and to the American embassy to ask for an explanation.
"He appears to have been turned back at Atlanta airport with no clear explanation, and he has been handed no documentation," he said.
"All he has is a hand written note that has been entered into his passport by an official in Atlanta.
"I don't see why our citizens should have to put up with it."