Officers found the woman’s body at a property on Mountain Highway near Dorset Road in Bayswater just after 11am.
A 39-year-old man from Bayswater was arrested nearby about 11.40am.
He is expected to be interviewed this afternoon.
Police said it is believed the parties are known to each other.
A crime scene has been established, and the investigation remains ongoing.
Anyone who witnessed the incident, with footage or further information is urged to contact Crime Stoppers on 1800 333 000.
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