A spokesman said one of the corpses was due to be sent to a funeral parlour on Wednesday while another was to be cremated after a memorial held at the hospital.
Members of the two families completed procedures to collect the bodies around the same time.
Staff at the hospital mortuary were later notified that the corpses had been swapped and that the body that had been sent to the funeral parlour was the wrong one.
The body that should’ve been sent to the funeral parlour had been cremated when the mistake was spotted, the hospital said in a statement.
The hospital said it’s highly concerned about the incident. It said it had contacted and met with the affected families to express its apologies and condolences, adding that it would offer them with the necessary assistance.
Tuen Mun Hospital said it would set up a panel to investigate what went wrong and review the procedures of handling bodies.
It added that four staff members linked to the incident have stopped carrying out relevant duties.
“Staff are reminded to prudently handle the process of body claiming and reinforce the identification of deceased bodies,” the spokesman said.