Up to 20 members of Our England Today waved placards and St George's Cross flags at KFC in Deepdale Shopping Park, Preston, on Friday
The restaurant is one of around 80 outlets across the country taking part in a trial following requests to provide halal food in parts of the UK.
Officers from Lancashire Police attended and several of the group's members were kicked off by retail park security staff for drinking cans of lager. They handed out leaflets, put them on car windscreens and tried to dissuade customers going into KFC.
Louise Nixon, 39, from Freckleton, near Preston, said: "They were just saying, do you know it's halal meat or something. They tried to give me a leaflet but I didn't take it, it might put me off. It's the first I knew about it. The girl inside said it changed in February. I don't think the protest is very nice really."
A police spokesman said no arrests were made and the group left after around an hour to go to a nearby pub.
Halal meat means the animal has been killed in accordance with Islamic dietary laws. Traditionally, it is killed by hand and must be blessed by the person doing the job. But some Muslims, including the Halal Food Authority, say a mechanised form is also now acceptable. KFC recently met with the Lancashire Council of Mosques to defend its halal chicken products.
The group, mainly young men, some with children, said the protest was not an English Defence League (EDL) demonstration. However it was advertised on an EDL social networking website page and a statement on their website said: "We would like to encourage "flash demos" at these restaurants".
An Our England Today spokesman said: "This KFC has taken it upon themselves to serve Halal. We were not asked, we had no choice and if we want to eat KFC we have no choice other than to eat Halal."
A KFC spokesman said: "Although these stores are now halal accredited, we are still offering the same great tasting chicken and meeting the same high standards of animal welfare that we always have and, wherever possible, we have made sure that a trial store is near a non-halal restaurant to give our customers a choice. We hope the majority will understand that we are offering halal food in a number of our restaurants in response to demand from our customers."
A Unite Against Fascism spokesman said: "This was a very small turnout, quite a pathetic demonstration, attempting to fuel hate and racism."
Lancashire Evening Post
Thanks to NewsHound for the heads-up