Police responded to requests of a welfare check at a house on Knight Street in Arncliffe about 2pm today.
The bodies of a man aged in his 70s and a woman aged in her 90s were located in different rooms.
They are believed to have been deceased for a considerable amount of time.
Forensics are on scene and detectives are investigating.
As investigations continue, police are asking anyone with information about the incident to contact Kogarah Police Station or Crime Stoppers on 1800 333 000.
