The country's health authority states that people were injured in an "incident" on Friday, without specifying what happened.
There were previously reports that a wall had collapsed at the Alejandro Villanueva stadium in the capital Lima, but this was denied by the home team Alianza Lima.
The incident is said to have occurred at a gathering before the derby match.
"There has been an unfortunate incident at the stadium where 47 people have been injured, and unfortunately one person has died," Health Minister Juan Carlos Velasco told the media.
