101-year-old Alexteen Roberts (pictured above with her daughter) has called her attacker a "wicked man".
She was followed on her way back from a prayer meeting and pushed to the ground, punched in the ribs, then had her handbag with £300 inside stolen.
Ms Roberts is a Seventh-day Adventist and had been at her church on Holloway Road, Islington, in north London.
The suspect pretended he was a council worker, saying he was there to fix her electrics before the assault in Tottenham on August 23rd.
Ms Roberts, whose 101st birthday was on Wednesday, said: "I'm a bit shaky. When I'm coming in the house now I'm afraid because of this wicked man."
Alexteen Roberts holding her 100th birthday card and letter from Queen Elizabeth II.
Her grandson Ashley Aitcheson, 31, who was inside the house, said he heard his grandmother shouting in "distress" at around 5pm and raced out.
He managed to punch the robber and break his aviator sunglasses during the chase but said he "knew all the little side streets" and managed to get away.
Ms Roberts was taken to hospital as a precaution and escaped serious injury but suffered bruised ribs.
Her grandson, Mr Aitcheson, said the man looked like "a drunk" was white, around 35, with baggy clothes and a beard.
Detective Chief Inspector Luke Marks said: "This was a despicable attack on a very elderly lady who lived independently and is now fearful to return home.
"She is naturally extremely distressed and shaken by what happened and we are appealing for help to catch his man before he targets someone else."
The attacker was last seen heading north towards Seven Sisters Road.