Police called to the property in St George's Hill, Weybridge, at about 10:00 BST by ambulance crews also found a man in his 30s with serious injuries.
Formal identification has not yet taken place, Surrey Police said.
St George's Hill is a private, gated estate with a golf club and tennis club, where six-bedroom homes are listed for about £14m.
Det Ch Insp Jason Taylor said officers believed they knew the identity of the woman and the man, who was taken to hospital for treatment.
He said next-of-kin had been informed.
"The investigation into this tragic incident is still in the very early stages but at this time I believe this to be an isolated incident,"  the detective said.
The 964-acre estate is described by the St George's Hill Residents' Association as having been "designed for driven, motivated and successful high achievers".
A murder inquiry is under way after the body of a woman in her 30s was found at a house in an exclusive part of Surrey.