Liniers, in the fifth tier, have been at their home ground since 1987.
One half is much shorter than the other, and the Argentine Football Association is threatening closure if it is not corrected by 15 December.
Club president Marcelo Gomez said officials realised the field was crooked after seeing aerial images on Google Maps.
But manager Cesar Aguirre does not believe it poses a problem.
"We've played here for so many years that we've adapted to its shape," he said.
"Maybe it's the opposition team who need a couple of minutes to get used to the field. But tactically it does not change much."
Liniers vice-president Miguel Narvaez explained how the wonky pitch came to be.
"This is a story that began 30 years ago," he said. "In 1984-85, a couple of old visionaries bought seven and a half hectares.
"They began the works, they laid the pitch, and at that time there were no lasers.
"They pulled the string line and it seems they did it a bit crooked. Now we are now working to fix that."
Fifa regulations state that pitch markings should be "rectangular and marked with continuous lines which must not be dangerous".
A club in Argentina has been ordered to fix the wonky pitch they have been playing on for almost 30 years.