The Winnipeg Police Service's bomb unit was called in on Saturday afternoon, after family members found the device while cleaning the residence's attic around 2 p.m. CT, according to police.
Const. Jason Michalyshen said the bomb, which was a 46-centimetre cylindrical device, was safely removed from the home where it was found.
There is no indication to date on why the bomb was there or whether it is dangerous. Police continue to investigate.
It's the third time in a month that police in Manitoba have had to deal with a potentially explosive object.
Earlier this month, a Winnipeg police station was shut down for almost two hours after somebody brought in an item that officers deemed to be dangerous.
The man who brought the device to the Lyle Street station had thought he was doing police a favour. Police later said the object was deactivated.