Julian Newton was ejected from the store in Denton, Greater Manchester, after he refused to leave following customer complaints, a spokesperson for the retailer said.
In footage posted on social media, a security guard is seen pushing Mr Newton away as he tries to re-enter the shop.
“I’m going to have a cup of tea,” says the candidate, who is standing to be an MP in the neighbouring constituency of Stalybridge and Hyde.
“You’re f**king not,” responds the guard.
As Mr Newton again tries to go back into the store, another man, who appears to be a bystander, pushes him back and tells him: “There’s kids in there, f**k off – you’ve been told.”
The Brexit Party candidate makes a final attempt to barge past the security guard, shouting: “I have a right to have a shop in the local Morrisons store. I’m going to have a cup of tea, I’m starving.”
He then falls to the ground as the guard restrains him.
A Morrisons spokesperson said: “Customers in our store complained about the man in the video because he was forcing leaflets onto them. Electioneering doesn’t take place in our stores. He was asked to leave the store but wouldn’t.
“The security guard, who is from a security company, overreacted and we are dealing with this.”
The video, filmed earlier this week, ends with Mr Newton handing a Brexit Party leaflet to the man filming the confrontation.
It is unclear who recorded the footage, which has been circulated on social media some of the party’s candidates and supporters. Some viewers said the video was "clearly staged".
Many Brexit-supporting accounts shared the video along with baseless claims that Mr Newton had been ejected because of his political views, and began using the hashtag #BoycottMorrisons on Twitter.
The hashtag was soon flooded with posts poking fun at the Brexit Party. One tweet read: “When Morrisons asks you to leave you should already know leave means leave.”
In a statement issued by Tameside Brexit Party, Mr Newton said he had been attempting to enter the supermarket to buy a cup of tea for a homeless man he had seen sitting outside the store. “He was done and contemplating the end,” he claimed.
The homeless man is not seen in the video, which shows a view of the shop's entrance.
Mr Newton said the security guard “turned on” him when he was “doing nothing other than talking to shoppers and caring for a weak and vulnerable person”.
He said had reported the incident to police. Greater Manchester Police did not immediately respond to a request for information.
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