Dunne Stores, Gorey Shopping Centre closed until further notice; sign on the store window.
The Union says the supermarket is using the livelihoods of more than 100 workers as a protest against the injunction.
Mandate General Secretary John Douglas, said the company’s behaviour is "despicable and grossly irresponsible".
“There are 100 families in Wexford who have no idea whether they’ll have a job next week or not. All because Dunnes Stores have broken a lease agreement with their property management agent and they stubbornly refuse to abide by a Court injunction,” said Mr Douglas.
“This shows the level of contempt Dunnes Stores have for their own staff and the arrogance they have when it comes to abiding by the laws of the land,” he said.
Mandate say the company must do the responsible thing by immediately engaging with the workers’ representatives and the property management agent to protect the business.
Mr Douglas added: “The anxiety, uncertainty and stress this has caused those 100 workers in Gorey is unnecessary and unacceptable.
"Senior management in Dunnes Stores should be ashamed of themselves.
"It’s bad enough that the company won’t give their workers secure hours and a living wage, but now they’re playing games with people’s lives over a side entrance to the business.”
Workers were today told to show up for work as normal despite the store being closed.
One worker, who did not want to be named, told independent.ie that management told everyone that "their jobs were safe".
But he added that they refused to put this into writing.
"We were told to pack up all the perishable items that were sent away on a truck first thing," she said.
"But so far all the other stock seems to be staying put. Dunnes have put a lot of money into this store recently. This was one of their better and more successful outlets.
"They referred to it as an A-Grade store which would be up there with Cornelscourt in Dublin.”
Local councillor and Wexford County Council Chairperson Malcolm Byrne has urged both parties to resolve this issue.
“The big challenge seems to be there is an unwillingness between the shopping centre management and Dunnes stores management to resolve this.
"The ones who are caught in the crossfire are the workers and their families.
“The store is in no financial trouble, it’s a good store in a thriving market town, I hope both sides will sit down and common sense will prevail."
Damien Furlong, who has worked with the company for four years has said the actions by the company were "out of line."
"I still have not been officially told what the situation is, no one has bothered to contact me."