A deceased patient who had no relatives was left in a room for days at the Örebro University Hospital before staff realized the body was still there.
The patient died soon after being admitted to the intensive care unit in late May.
Hospital staff put the body in a room where friends and relatives can go to say their final goodbyes. But the patient had no relatives and staff simply forgot the body was in the room - until five days later when another deceased patient was brought in.
In that period, nobody had come to say their goodbyes to the dead patient.
"What happened is terribly unfortunate and the fact that the patient lacked relatives is a factor but it still should not happen," Anders Nydahl, head of the hospital's anesthetics and intensive care unit, told local newspaper Nerikes Allehanda (NA).
"I have worked here for 37 years and this has never happened before," he added.
Normally, a deceased patient should only stay in the room for up to six hours and then be brought to the pathologist.
"Things happen to the body and had the room temperature been higher the consequences would have been worse. In this case not much had happened to the body," said Nydahl.
The hospital launched a review to try to find out what went wrong. The ward has since improved its routines to prevent a similar incident from happening in the future, it said.