The Advertising Standards Authority has received 78 complaints about the ad, created by Delaney Lund Knox Warren, since the end of October.
The cow walks across a field in the background of the ad, which continues the series of spoof musical ads based around Burger King's 拢1.99 promotion. Its cover is emblazoned with the Burger King logo.
An Irish folk singer is shown walking in a field singing "They're only one ninety-nine", and a voiceover highlights Burger King's freshly baked Fiery Barbeque Beef baguette.
Complaints mainly centre on the fact that it is offensive to use a cow in an ad for a burger chain, with some of the complainants saying that they are vegetarian.
There are no plans to withdraw the ad before the ASA has made a ruling on the case.
"Our latest advertising campaign was intended to be light hearted and not to cause offence to anyone," a Burger King spokesperson said.
If you have an opinion on this or any other issue raised on Brand Republic, join the debate in the .