Jonny McFadden, who runs the Star Inn in St Just, Cornwall, told CNN that he installed the electric fence in front of the pub's bar for social distancing purposes.
"It's a very small pub, the first and last rural pub in Cornwall," he said.
England's pubs were allowed to reopen their doors on July 4, after being closed during the UK lockdown. Social distancing remains mandatory, and customers must hand over their contact details before they enter to help with coronavirus tracking if needed.
McFadden told CNN that the idea to use the fence came as he was preparing to reopen the pub.
"To protect staff and myself and my customers you have to put in the meter [distancing] rule," he said.
McFadden said he wanted "to put some rope, or chain" to make sure customers kept back from staff at the bar but couldn't find suitable equipment.
"I thought, this is not going to keep them [the customers] back," he said. So instead, he opted for the fence to see "what that does."
The fence is not usually turned on, but the sight of it has managed to deter some customers from crowding near staff.
"It's not on but it's got the desired effect that everybody thinks it's on and they keep well away from it. It's the fear factor. It's working very well," McFadden said.
At least three pubs in England have had to close their doors again, after customers tested positive for coronavirus.
Asked how customers reacted to the innovation, McFadden said: "It was quite comical. We're in a rural area so everybody knows what an electric fence is. I got a little sign too on it - 'electric, danger."