Police discovered the decomposed body on Murdoch Drive yesterday.
A woman may have been living with her partner's decomposing body for several weeks before police were notified.
Their Murdoch Drive home was declared a crime scene after Police made the discovery yesterday morning.
A man in his 50s was found dead, but due to the recent hot weather authorities said it was difficult to know how long he had been dead.
The woman living in the Greenfields home did not report the death but is not being treated as a suspect in relation to the man's death.
Items were removed from the Mandurah home, an autopsy will be done to determine how the man died and a report for the Coroner will be prepared.
More to come.
Mandurah's Bar Therapy damaged by fire
Postman injured in Wannanup crash
Man charged after allegedly stealing service medals from Greenfields storage unit
South West resort receptionist charged with 32 fraud offences
Daughter of Port Kennedy hit-and-run victim pleads for offenders to hand themselves in
Concerns for missing woman last seen in Mandurah
Mandurah woman wanted for questioning over current investigation
Investigation underway into Bunbury sexual assault
Two motorcyclists seriously injured in separate crashes