The attack happened between 11.30pm on Thursday, 1 September 1 and 12.20pm on Friday, September, 2 in Heddingham Close, Islington.
The victim - a woman in her late 50s - was walking in Wontner Close, Islington when she was confronted by a man who asked her for some change.
The woman gave the man what change she had. At this point he grabbed her by the shoulder and pushed her into Heddingham Close. Once there, the suspect pulled out a knife, and threatened her before raping her.
After the attack the suspect emptied the victim's bag onto the floor, taking valuables before making off on foot towards Popham Road, Islington.
The attack was reported to police soon after the attack and the victim was taken to a specialist care unit by attending officers.
No arrests have been made. Enquiries are ongoing.
The suspect is described as a dark-skinned black man, between 5ft 4in to 5ft 6ins of medium build wearing dark clothing, either black or dark blue. He is believed to be aged between 30 and 40 years.
- Information to the Sexual Offences, Exploitation and Child Abuse Command on 0208 733 5999 or call Crimestoppers anonymously on 0800 555 111.