The men forced their way in after tricking the victim into opening the door, the Metropolitan Police said.
One of the burglars sat on her chest to hold her down while jewellery was cut from her wrist.
The victim - a woman in her 80s - had a sock stuffed in her mouth and was told not to speak during the ordeal at her home in Plaistow, Newham, on Thursday evening.
The five suspects are described as while males in their 20s wearing black clothing.
One was wearing black Nike tracksuit trousers with red piping.
Police were called at around 7pm on Thursday, and it is estimated that the burglary lasted for 20 to 30 minutes.
The incident is being investigated by the Met's North East Burglary and Robbery Unit.
Anyone with information is asked to contact police on 101 quoting reference CAD 006400/21JAN21 or contact Crimestoppers anonymously on 0800 555 111.
There have been no arrests and inquiries are ongoing.