Police said she was found seriously injured at an address in Kilmarnock on Tuesday night.
She died in hospital a short time later and the man, 51, was arrested and charged.
A spokesman for Police Scotland said: “Around 10.20pm on Tuesday evening, police were called to a report of a woman seriously injured within an address in Craigie Place, Kilmarnock.
“She was taken by ambulance to Crosshouse Hospital where she died a short time later.”
The man is expected to appear at Kilmarnock Sheriff Court on Thursday.
A report will be sent to the procurator fiscal.