The woman answered her door to the bogus caller, dressed in black clothes, at about 2pm on Thursday April 13, just off the A904 near Newton.
She called police after becoming suspicious when he claimed to be an officer.
He is described as white, around 50-years-old, approximately 5ft 5ins tall, of slim to medium build with short white or grey hair and wearing black boots, black trousers and a black sip up top.
The vehicle he drove to teh woman’s house, between The House of the Binns and New Hopetoun Garden Centre, is described as a dark green Ford Focus 08 model with a black petrol cap.
“The member of the public was rightly suspicious of the motorist and reported this matter to the police,” said Sergeant Phil McIntosh.
“Inquiries into the full circumstances surrounding the incident are ongoing and anyone with information is asked to come forward.
“I would like to reassure our communities that any genuine police officer will present appropriate identification if approaching you and you can confirm their authenticity by contacting our non-emergency 101 number.
“If you are approached by anyone who identifies themselves as an officer but fails to produce ID then contact police immediately.”
Anyone with information can contact Police Scotland on 101 or alternatively or the charity Crimestoppers anonymously on 0800 555 111.