The mass grave was discovered by archaeologists from Sheffield Uni at the site of a 14th-century hospital at Thornton Abbey, near Immingham in North Lincs.
It is believed the bodies of 48 corpses – including 27 children – were buried in the pit during the Black Death.
The devastating disease killed an estimated 75 to 200 million people across Europe between 1346 and 1353.
The team said they sent teeth samples from the skeletons found in Lincs to McMaster University in Canada where ancient DNA revealed traces of bacteria responsible for the deadly plague.
Dr Hugh Willmott, Sheffield University”s Department of Archaeology, said: “It is estimated that up to half the population of England perished during the Black Death but mass graves are extremely rare in this country.
“It seems local communities continued to dispose of their loved ones in as ordinary a way as possible.”
The gruesome discovery dates back hundreds of years into British history but mass graves are still being used.
Depraved ISIS sickos recently turned a school into a “killing field” as they tortured captives before shooting them.
The Sheffield Uni project will feature on the BBC”s Digging For Britain programme on December 13.