Supermac's has been told to remove its shopfront from its Temple Bar outlet as it's too "traditional" in style.
Despite being located in the heart of the historic tourist area, Dublin City Council is objecting to its signage after deeming it inappropriate.
The council has also cited its sister outlet Papa John's on Essex Street East as being out of place in the conservation area. The decision is being appealed by the fast-food chain.
When Supermac's first took over the premises, they changed the modern steel and stone shopfront to a more traditional front.
However, it made the change without seeking permission from the council.
Last April, it applied to retain the shopfronts and signs but the council refused.
The planner's report said that the use of a "reproduction traditional-style shopfront is inappropriate in this modern four storey building".
It also said the style of lettering was not of a "sufficiently high quality" for the location.
In its appeal to An Bord Pleanála, Supermac's said its shopfront was made of wood with a "colourful presentation" and more in keeping with the street than the original steel finish.