Officers told a woman in Peterhead, Aberdeenshire that her brother had passed away as the result of a "sudden, non-suspicious death" in Aberdeen on Sunday.
However, it later emerged that with "limited information" the force had made an error in identifying the next of kin.
The error is the latest in a series of high-profile mistakes since the creation of the national force in 2013.
The family of the man who died have now been informed.
Chief Inspector Neil McDonald said: "During the afternoon of Sunday 3 September, Police Scotland attended the sudden, non-suspicious death of a man in Aberdeen.
"Unfortunately there was only limited information available as to the identity of the deceased and police commenced inquiry to establish details of his next of kin.
"As part of that inquiry, officers attended at an address in Aberdeenshire where they believed deceased's immediate family resided. Unfortunately, it was established that this was not the correct next of kin.
"The error was quickly identified and I have reviewed the circumstances with it appearing to be attributable to human error.
He added: "Whilst I am content that our officers were attempting to identity the next of kin in difficult circumstances, this should not have happened and a supervisor has met with the affected family and apologised to them."